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PICList Thread
'[OT] Intrinsic safety & Gasoline pumps [TECH non'
1999\10\12@163355 by Russell McMahon

picon face
>And how to get "the smallest sparks"? We can have very small sparks even
>with very low voltages. To have a spark is necessary to have an electric
>field higher  that a determined value that depends on the material:
>dielectric rigidity .
>So, to have a very small spark in a gas with a small induced voltage is
only
>necessary to have a very small gap between two electrodes with a difference
>of potential.

Yes.
I should have mentioned "intrinsically safe".
I'm not expert in the details but it is "known" that if you limit available
energy then you can produce an electrical situation where there is not
enough energy available for ignition.
Such equipment limits both maximum possible voltage and current inside the
safe area.
A web search for 'intrinsically safe" will turn up more than you ever wanted
to know on the subject.

Equipment in eg Petrol Pumps is either intrinsically safe OR operates in
mechanical containment which is guaranteed not to allow ingress of flammable
gas mixtures. I would have thought this would be an extremely difficult task
indeed, but as I have never seen a petrol pump dismantle itself explosively
and as the pump energy is well above intrinsically safe levels I guess this
means that they have got it down to a fine art.



regards


     Russell McMahon
_____________________________

>From another world - http://www.easttimor.com

What can one man* do?
Help the hungry at no cost to yourself!
at  http://www.thehungersite.com/

(* - or woman, child or internet enabled intelligent entity :-))

'[OT] woof, splat [TECH non electronic]'
1999\10\12@190328 by Dennis Plunkett

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At 11:48 12/10/99 +1300, you wrote:
{Quote hidden}

There are some methods for welding tanks, one of them is to connect the
tank to a vacum cleaner, another is to connect it to a exhaust, and yet
another is to fill it with water, and then there is the fill it completly
with petro. All of these methods will at one time or another cause the
welder to be painted onto the roof of the welding room! (Much like a
painting my Mr. Heart)
The *only* common in use method that works is to hot tank, the tank in
caustic for 12 hours!


Dennis


>
>
>      Russell McMahon
>_____________________________
>
>

'[OT] [TECH]From Engine to Caboose, What's in the t'
1999\10\12@192830 by Dennis Plunkett

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At 11:09 12/10/99 -0400, you wrote:

Time for my input!

Ok all seem to go along the same lines.
But (Always a but)
None of the systems are fault proof
None of the systems indicate full sting connection

To do this imagine:-

Engine (Does not matter if there is more than one, but this is the master
controller)
cars
End of train (Not all tranis have a cabose!)


The end of train marker will provide the loop back point (This will also
alow the system to verify that the train is intack (A problem faces when
passing loops are used Ask Annie!)) This will loop the data directly back
to the master

The master end starts sending out NULL byte
Each other item in the link will pass the Null bytes on
The master then counts the number of bytes that it takes to get the NULLs
back i.e. The system is a full loop and the master will then KNOW how many
carriges, and the expected train length.
The mater then sends out the start of message byte.
Each carrige will see this and know that it has to send out its own address
(Value). The second byte from the maste will have the number of expected
carriges, and the third byte has the current carrige number.
The current carrig number is incremented by the current carrige and points
to where in the stream it will place its address. All carriges will inspect
the current carrig number and the expected number, if the current is
greater it will hold the data line low (Clock NULLS to indicate an error)
etc...
There are many other things that you can add to this to improve the
reliability. You must remember that this is to be a failsafe system, and
should report an error if it is not working, no assumptions can be made!


Dennis





>
>

1999\10\12@193915 by Dennis Plunkett

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At 12:23 12/10/99 -0700, you wrote:
{Quote hidden}

Thompson couplers come to mind I think that ABB make these now, but the
cost is a bitover the top, and requires that the knuckle couplings and
bumpers be removed (Too expensive)


Dennis

'[PIC][admin][OT][TECH][FLUFF][WHINE]and 18F87x ava'
1999\10\13@123452 by mjurras

picon face
How about we add [WHINE] to the headers for all you guys who constantly bitch ab
out how the list
isn't formatted exactly to you specific wants for efficient reading. This will g
ive you something
to look forward to reading.

Or, maybe you could just learn to deal with it. It isn't that hard. If you can't
go to onelist.com
and start your own.


Now for some real content. I am starting a new design and have been noticing pos
ts about the lack
of availability of the 16F87x. Digikey also shows naught available. Should I lea
ve my ICD in the
box and use an available part or is the 16F87x going to be available 1Q 2000?

- -Mark
__________________________________________________
Do You Yahoo!?
Bid and sell for free at http://auctions.yahoo.com

1999\10\13@185355 by Tony Nixon

flavicon
picon face
Mark Jurras wrote:

> Should I leave my ICD in the box and use an available part or is the 16F87x go
ing to be > available 1Q 2000?

That's probably where all the stocks of F87X chips have gone. Into the
Microchip ICD's :-)

--
Best regards

Tony

http://www.picnpoke.com
Email spam_OUTsalesTakeThisOuTspampicnpoke.com

'[Tech] Metcal special: Buy 4 SP200's, get one free'
1999\10\23@065230 by Mark Willis

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face
Metcal's having a sale on these fairly decent soldering irons, though
MSRP of $299 is a little steep.  Looking at an MX500TS Talon unit,
myself <G>  It's linked off http://www.metcal.com/.

"Promotion ends March 31, 2000. Available only in the Americas.", of
course.  If anyone wants to know what the best pricing I can find is,
just ask.

 Mark

'severe conditions[TECH]'
1999\10\25@152155 by Anne Ogborn

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Anybody designing equipment for severe conditions,
there's a small electronics firm in Greenland.

They advertise that their specialty is designing equipment
for severe environmental conditions.

I'd believe it!


'[Tech]PLCC Prototyping'
1999\12\09@213300 by Thomas Brandon
flavicon
picon face
I am looking at using a number of devices (CPLDs mainly) that are PLCC only
(at best). From searching the PICList archive I believe with a nice fine
soldering iron, flux and a bit of practice the PLCCs could be hand soldered
to a PCB. However, in prototyping I would far prefer to be able to
breadboard rather than having to make many prototype PCBs.

So, I would like devices that will allow me to breadboard with PLCCs of
44pins (minimum) hopefully all the way up to 84 pins. The best idea I can
think of is a small PCB with a PLCC socket in the middle (preferably ZIF but
due to cost maybe only LIF) and pin headers around the outside for
connecting to standard proto board. Now this shouldn't be too hard to
design, the problem is the construction of the PCB. I have little enough
experience doing non SMD scale PCBs so attempting a SMD scale PCB is not
neccesarily high on my list of priorities. Regardless any info on the
feasability of home producing SMD PCBs would be appreciated (i.e. how fine a
pitch can you manage?, what goes wrong with finewr pitch?, what equipment is
needed etc). But, for the moment I would prefer a premade PCB. Does anyone
know where such a PCB could be obtained and an approximate cost.

Oh yeah, and is it possible to do all this with a 100pin TQFP?

TIA,
Thomas Brandon.

1999\12\10@193819 by Mark Willis

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face
Lots of pre-made PLCC adapters out there;  Newark's catalog is handy, P.
609, has these for several SOIC packages, $1.39 to $6.49 in 1's.  And
for up to 20-pin PLCC's, $6.49.  Don't see any there for PLCC-44's.
Jameco has these with sockets for about $7, on looking more.  Many of
the SOIC units are designed for "sacrifice one, solder it to the board"
type work.

PLCC can be done at home by using 1-sided PC board and a "Sharpie"
marker, drawing the traces freehand, and then drilling through holes for
a .1" header of some kind & soldering IC/header onto the board.  If you
have shakey hands, good luck. <G>

(I didn't say it's EASY, you'll notice;  Expect to get Writers' Cramp
<G>  And expect to go through with a dental pick and clean up the
traces, as needed;  PLCC traces are pretty fine & close together, 25 mil
width on 50 mil centers, same as SOIC's.  {1 mil = 0.001" in my
terminology here.  I use mm for millimeters.))

http://www.pcdmag.com/resources/smt/ is a good place to look up pad
specs, BTW.

The Press'n'Peel type sheets can do these pretty easily, I imagine;
Need to get some & work with them.  For darn sure, the Phototypesetters
out there can make film for you that'll do this nicely!  Doing this with
tape and pad outlines on film then photoreducing can be done too, "but
why!?"  <G>

TQFP, that's 12 mil traces on 25 mil centers, get a magnifying glass if
you try this manually - lay off the Coffee, lay in a stock of Aspirin
too, and make an appointment with your massage therapist and
optometrist  <G>  As a 300 DPI laser has 3.33 mil pixels, that's 3 to 4
pixels wide, and should do OK with the Press'n'Peel type film.  A 600dpi
laser would be better here.

 Mark

Thomas Brandon wrote:
{Quote hidden}

--
I re-ship for small US & overseas businesses, world-wide.
(For private individuals at cost; ask.)


'Analog MUX ON Resistance Variations [Tech]'
2000\03\23@183512 by Brandon, Tom
flavicon
picon face
Looking at a ADC application measuring voltages generated by pots. Looking
at something like 64 channels so 2 levels of 8ch Analog MUXing. I'm
wondering, what sorts of variations am I going to see in ON Resistance? The
Analog Mux I'm looking at (Philips 74HC4051) specs. something like 9 Ohms
variation in ON resistance between any 2 channels.

What I want to know is:
1) What sort of variations am I going to get between channels on different
ICs? They spec ON resistance as varying by up to 180 Ohms from the specs.
2) What factors will effect the ON Resistance of the MUX during operation?
i.e. is temperature going to have a large effect on ON Resistance? What
about the signal, wil the signal type effect ON resistance?

The application only needs 7bits accuracy (having 14bits would be nice too)
as it's MIDI but it needs to be a very consistent 7bit. Cause there's only
128 positions, 1 position is important. There can't be any drift and ideally
all channels would be highly equivalent in terms of position -> value.
Obviously some sort of calibration will be neccesary I'm just trying to get
an idea how often I'll need to calibrate and if it's wirth compensating for
external conditions.

Anyone have any data on this sort of thing (just general datas fine doesn't
have to be specific to this chip)? The philips data sheets don't provide any
info. on this sort of thing. About the only graph in the whole datasheet is
supply operating ranges.

Thanks,
Tom.

2000\03\23@195337 by Harold M Hallikainen

picon face
       The variation in ON resistance has no effect until you load the ouput of
the mux. The input of a PIC A/D is a pretty high resistance, much higher
than the mux. The other concern is OFF resistance or leakage current. How
will the voltage on nonselected channels affect the selected one?
       I have used one level of 4051's with 10K pots and gotten at least 8 bit
resolution with a 16c74 (I can get a stable reading with variation only
at the "bit boundary" areas of the pot).
       To get 64 analog inputs, how about a single level of 4051's driving 8
analog inputs on the PIC?  I did this for 24 inputs.

Harold




FCC Rules Online at http://hallikainen.com/FccRules
Lighting control for theatre and television at http://www.dovesystems.com

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'Audio DAC Accuracy [Tech]'
2000\04\04@214738 by Brandon, Tom
flavicon
picon face
I am looking at a project where I would like to synthesise various audio
waveforms. Looking at sine, square etc 20Hz-24kHz.etc. My question is in
regards to the accuracy of DAC needed. Now, typically Audio applications use
16+ bit at 44.1 and up. I have no problems with the sample rate, it has to
be at least double the highest  frequency of interest and close to double
will produce very low quality sine waves (e.g. CD audio, 20kHZ sine @
44.1kHz = ~2.2 samples\cycle) hence most audio converters use 8 to 16x
oversampling so you're looking at about 350kHz (44.1 @ 8x).

But what effect will bit depth have on the reproduction? Obviously it will
introduce larger step sizes and thus less smooth curves. If you're
reproducing complex signals I could see it effecting the
reproduction\capture of appropriate sines. Slight nonlinearities may not be
able to be filtered out as easily due to the complex source. But, Ig all
you're producing is single oscillators then what sort of accuracy would be
needed?

Also, for the same project I'd like to use 1 DAC to drive a few SHAs to do
mutlichannel. I've seen one SHA capable of >12bit (an Analog devices 16bit
SHA) based on DNL and this was only single channel. Does anyone know of a
multi channel SHA with a DNL suitable for 14+ bits ideally with settling
time to suit 1-2MHz. Also, I'm still looking for a DAC capable of 14+ bits @
>1MHz at a reasonable price.

Thanks,
Tom.

'[OT] RE: Audio DAC Accuracy [Tech]'
2000\04\04@230522 by Plunkett, Dennis

flavicon
face
The first and most important question that you have to ask is how colse to
the original does it have to be? If the original is sampled at 44.1KHz, then
unless you are going to interpolate the results to increase the sample rate
then nominal audio type sampling is OK. (You atempted to cover this in your
8 to 16x bit)  However if you want to also provide the high frequency
transient responses then the sample rate has to be very very high (Around
2mHz).
Whichever you use the reconstruction filers will be the bigest bottleneck, a
4 to 6pole butterworth should do the job.

Also note that there is a big difference between the SHA accruacy and the
rate of change that  it will respond to.


Dennis




> {Original Message removed}

'Audio DAC Accuracy [Tech]'
2000\04\04@230533 by Don Hyde

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The relationship between DAC bits and SNR (signal-to-noise ratio) is
actually pretty simple.  SNR is normally expressed in dB, doubling the
voltage of a signal increases its level by 6 dB (approximately).  The SNR of
a signal produced by a DAC is the ratio of the maximum signal output to the
step size.  Adding a bit to a DAC doubles the ratio of full-scale output to
minimum step size, therefor it increases the SNR by 6 dB.  An 8-bit DAC has
an SNR of 48 dB, which sounds pretty good (telephones use 8 bits at 8K
samples/second), but not as good as your stereo.  On a good day, FM radio
can give you 70 or 80 dB SNR (equivalent to around 12 bits at 30K samples or
so), which is not as good as a CD which, with 16 bits can give you 96 dB
SNR, which is better than almost anyone's ears.

120 dBA (absolute sound pressure) is often considered the threshold of pain
(I think mine is lower, but I guess it's pretty subjective).  A quiet room
might get as low as 40 dBA, so you probably have never experienced more than
about 80 dB SNR in real life, which is the reasoning behind the choice of 16
bits for CD's -- more than you get in real life, with some to spare.

> {Original Message removed}

'Graphic LCD Design Software [Tech]'
2000\04\05@214139 by Brandon, Tom

flavicon
picon face
I am currently looking at putting together a Graphical LCD design tool. I
had a look around on the web but all I could see was bitmap->binary
converters. What I'm looking at is a fully sprite based LCD design tool.
i.e. rather than designing everything as bulky, wasteful frames, ala most
software, you create your interface from sprites. For instance if you want
an arrow to come in from the bottom right hand corner rather than creating
10 frames with the arrow in various positions, you create an arrow sprite
and move the sprite across the screen. That way, to move a 4x4 pixel arrow
across a say 100x100 screen in 10 frames you only need 16bits storage + a
few for the animation info (this could be as few as 7 bytes, 3 bytes for
start (1 byte sprite, 1 byte X, 1 byte Y) position, 3 for end position, 1
for no. of frames) instead of 100000 bits (100x100 x 10frames).

Does anyone know if there's a package such as this out there? Anyone know of
similar projects I could get ides from? Any suggestions?

Currently doing it in VB but I'm thinking of using VJ for the logic so if
someone wanted to they could do a Swing interfaced cross platform version (I
personally dislike Swing as for me it simply doubles the development and
running times compared to VB which only doubles the runnning time (not even
double with native code)).

Tom.

'Audio DAC Accuracy [Tech]'
2000\04\06@035916 by mike

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face
Hi Tom,

I'm not really (infact not at all)a DSP expert but as I understand it the
answer to your question actually has more to do with the filter at the
output of your DAC and sampling rate than anything else. Additional bits in
your D-A do not as I understand it buy you a better reconstructed output but
greater dynamic range.

An over-sampling D-A converter interpolates it's output between sucessive
samples based upon a particular filter function (it doesn't just output the
same voltage 8/16 sample times). The idea is to offload some (most) of the
filtering from the analog output.

Sampling theory says that ANY complex waveform with spectral components up
to 1/2Fs (half the sampling frequency) can be re-constructed using by a
number of independant sinusoids. The important thing to note is that these
sinusoids must always be lower than the nyquist frequency (obviously
otherwise there would be spectral components higher than the nyquist
frquency which we've already dis-allowed).

Essentially so long as your filter can re-create a sinusoid at the nyquist
frequency and below you can build any waveform  you like as long as it
doesn't contain spectral components above that frequency.

If you just want to produce a single sinusoid at a single output level then
1 bit resolution is plenty.
Think of it like this, if you had more bits and you were sampling an
(exactly) 20Khz sinusiod at (exactly) 40K samples/sec what would your data
look like ? It would consist of 2 different values dependent upon where in
the waveform the sample was taken but they would always be the same 2 values
(just like a 1 and a 0).

The very least you should expect your filter to do is get rid of any "steps"
in the output. If you picture such a waveform it should be fairly noticable
that the steps themselves must introduce some unwanted high frequencies into
your output (think of each step as half a square wave, not really accurate
but you get the idea, that rising or falling edge is pretty nasty spectrum
wise).

Conceptually the filter on an D-A is not just there to filter out the high
frequency components introduced by the D-A steps but also to re-build the
sampled data.

Your real problem as far as I can see is that you need to re-produce some
waveforms (such as a square wave or sawtooth wave with a fundamental of
20Khz) that have spectral components in excess of 20Khz.
A square wave or triangle for example is theoretically comprised of an
infinite set of odd harmonic sines' STARTING at the fundamental frequency.
In order to re-construct a decent looking square wave you might choose to
sample up to the 7th harmonic meaning you'll need around 300Khz bandwidth or
600K samples/sec.

If however you change the impulse response of your filter to corespond to
your desired waveshape you could probably build your tone generator a lot
more easily.

An alternative might be to look at a DDS synthesizer...

As I say I am not a DSP expert by any stretch of the imagination, if there's
something I've missed hopefully some body can fill in the gaps...

Regards,

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Mike Cornelius                  Internet: .....mikeKILLspamspam@spam@bytethis.com.au
Byte This Interactive           Phone:    +61 2 9310-2157
PO Box 1342 Strawberry Hills    FAX:      +61 2 9319-3948
NSW 2012 Australia              URL:      http://www.bytethis.com.au
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~



{Original Message removed}


'[OT][TECHO] 3 supernovae about to occur ?'
2004\10\02@091722 by Russell McMahon
face
flavicon
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2 X-Ray flashes bursts and a near Gamma Ray burster from different sky
regions.
Subsequent nova(e) or not will help settle best theory of linkages between
the three.

       http://www.spaceref.com/news/viewpr.html?pid=15170

____________________________

Russell's SciFi Ramblings:    Read at your peril :-)
They still haven't realised that Gamma Ray Bursters are the means of
providing the immense energy required to propel "star ships" (not as we know
them, Jim) to the requisite speed - within a very very very small distance
from the speed of light - required to get enough time dilation to provide
trips of suitably short relative duration. A GRB is seen when we are "on
beam" of a jet from a formative event. An X-Ray flash occurs when we are
somewhat off line. We may in due course encounter a "vessel" for which we
have seen a GRB - although it's unlikely and it would probably not be for a
few millions to a few billions of years from now, our time. We will never
see a "vessel" for which we see an Xray flash as we are too far off axis. A
'starship', unless it is on a terminal mission, will only enter a region
where a suitable nova can be subsequently initiated. We are therefore
unlikely to have any really close visits. Most species only employ GRB
propulsion for transporting payloads that are inherently unsuited to FTL.


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'[OT] [TECHO] PC Banter - Windows XP forum'
2004\10\04@051405 by Russell McMahon

face
flavicon
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PCbanter.net

"A Windows XP help forum acting as a gateway to the Microsoft community
newsgroups"


       http://www.pcbanter.net/

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'[OT][TECHO] Windows XP drivers repository'
2004\10\04@072416 by Russell McMahon

face
flavicon
face
Links to many Windows XP drivers

   http://www.windowsxp-drivers.com/
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'[OT][TECHO] Windows SP2 broke my printing'
2004\10\04@072418 by Russell McMahon

face
flavicon
face
*** PRESCRIPT ***

The following problem is now fixed. But I'll post this on the chance that it
may be of use to others.

__________________________________

Not 100% sure this is a Windows XP SP2 problem.
But about 99% sure.
Other users report a fault that sounds 100% identical

Didn't happen instantly. About 1 week after SP2 install.
An HP G85 printer connected via USB.
XP Home.

Printed OK one day.
Next printing attempt about ?12 hours later AFTER DAYLIGHT SAVING CHANGED
THE TIME (I wonder) resulted in:

- Printer appears present as usual.
- Applications detect no printer present.
- No printing.

Install new printer of same type using existing drivers - no good.
Install new printer with update HP XP driver no good (62 MB!)

No go!
___________________________

SO:

Uninstall all versions of this printer (I had multiple instances with
different parameters set).
Uninstall all related print 'servers' found at
   Start
     Printer & fax
       File
         Server Properties
           Drivers

Restart.

Create new printer server by installing new drivers from HP site (62 MB
download)
For G85 it's

   http://h10025.www1.hp.com/ewfrf/wc/softwareList?product=60399&lang=en&lc=en&cc=us&dlc=en&os=228

For other HP printers back up this address a bit.

Restart
Install printer(s) based on this server
Works

I also made a server by reinstalling the original HP drivers and this
doesn't work. It seems the original set is still broken.
It also seems they have to be removed initially before the new drivers will
work.

As with many such things, this was a voyage of discovery and there may be
some magic enabling step that i performed and am not aware of
SO
YMMV.



           Russell McMahon

Many XP drivers

   http://www.windowsxp-drivers.com/


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'[OT][TECHO] Failure to display embedded pictures i'
2004\10\06@053132 by Russell McMahon

face
flavicon
face
I regularly send out emails containing photos to about 60 recipients.
I generally embed the photos rather than attaching them, as in many browsers
and some webmail programs this allows them to be positioned relative to text
rather than appearing at the end. I am using Outlook Express under Windows
XP SP2.

All except one recipient seem to be able to view the photos OK.
One recent addition to the list reports that the photos appear scrambled.
The 'mime" format is being broken. But if his wife forwards the emails to
him he can view them OK. He uses XP Pro and Outlook.

Has anyone any suggestions as to why his system may behave this way. My
Googling hasn't turned up any likely leads.


       Russell McMahon





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2004\10\06@103533 by M. Adam Davis

flavicon
face
I would tend to ask questions about his email provider and possible spam
or virus scanning the provider may be giving.  Does his wife use a
different provider?

When forwarding outlook simply packages the message up as an attachment
- no changes.  I'd be interested in comparing the two email - one
directly from you, and one forwarded from his wife.  This should point
towards the problem.

-Adam

Russell McMahon wrote:

{Quote hidden}

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'[OT][TECHO] Human exosure to vacuum'
2004\10\10@183158 by Russell McMahon

face
flavicon
face
Excellent and very interesting page on "vacuum breathing" and other aspects
of human exposure to vacuum.

       http://www.sff.net/people/Geoffrey.Landis/vacuum.html

Don't try this at home!



       RM

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'[EE][TECH] FTP server for Windows'
2005\08\12@062005 by Russell McMahon
face
flavicon
face
Anyone like to recommend a (preferably free) FTP server for Windows.
There are many out there. I'm more interested in ease of ownership
than features. If I can have both so much the better.
Being able to read and write files remotely is about the extent of my
spec. Anything else is icing.

WAR FTP sounds OK

       http://www.warftp.org/

One slight detraction is the site's repeated attempts to download
double-click tracking material not only when you access the page (as
many sites do) but at ongoing intervals. Spybot deals with that, but
it's annoying.

Any favourites, and why?
For HTTP I'm using Apache under WinXP-home at present and it's
excellent. ie it "just goes" as expected.

While I'm here, thoughts on a suitable (again preferably free) Windows
based POP3 server? Again, ease of ownership is the primary factor.
This would probably be get used behind a web based email system which
forwarded to POP3 to give me some security against local outages.



       Russell McMahon

2005\08\12@081029 by Gerhard Fiedler

picon face
Russell McMahon wrote:

> Anyone like to recommend a (preferably free) FTP server for Windows.
> There are many out there. I'm more interested in ease of ownership
> than features. If I can have both so much the better.

If you have any Pro (2k or XP) version, try IIS... pretty easy, already
there, and if you're worried about security, FTP is not for you anyway. (I
don't want to get into a web/ftp server war here... but IIS is being used
successfully in large and safety-critical operations.)


> While I'm here, thoughts on a suitable (again preferably free) Windows
> based POP3 server? Again, ease of ownership is the primary factor.

You could try one of the Hamsters. Hamster is a news and email (pop3 and
smtp) server. It comes in two flavors: "Classic"
http://www.tglsoft.de/misc/hamster_en.htm and "Playground"
http://www.elbiah.de/hamster/index.htm. The differences between the
versions (both seem to be active) are subtle... I use the Playground
version as a local news server.

Gerhard

2005\08\12@081859 by Carey Fisher - NCS

face picon face
  > Anyone like to recommend a (preferably free) FTP server for Windows.
  > There are many out there. I'm more interested in ease of ownership
  > than features. If I can have both so much the better.
  > Being able to read and write files remotely is about the extent of my
  > spec. Anything else is icing.
  >
  > WAR FTP sounds OK
  >
  >         http://www.warftp.org/
  >
  > One slight detraction is the site's repeated attempts to download
  > double-click tracking material not only when you access the page (as
  > many sites do) but at ongoing intervals. Spybot deals with that, but
  > it's annoying.
  >
  > Any favourites, and why?
 
I really like WS_FTP from Ipswitch. ( http://www.ipswitch.com ).
I use the free version to upload files to our
website and it's super easy to use and flawless.
No spyware or any other malware.
Carey

2005\08\12@083038 by M. Adam Davis

face picon face
I've used http://www.xitami.com for both FTP and HTTP.  You can
disable the HTTP (or put it on a different blocked port) and simply
use the FTP server.

-Adam

On 8/12/05, Russell McMahon <apptechspamKILLspamparadise.net.nz> wrote:
{Quote hidden}

> -

2005\08\12@093411 by Tim N9PUZ

picon face
Russell McMahon wrote:
> Anyone like to recommend a (preferably free) FTP server for Windows.
> There are many out there. I'm more interested in ease of ownership
> than features. If I can have both so much the better.
> Being able to read and write files remotely is about the extent of my
> spec. Anything else is icing.
>
> WAR FTP sounds OK
>
>        http://www.warftp.org/
>
> One slight detraction is the site's repeated attempts to download
> double-click tracking material not only when you access the page (as
> many sites do) but at ongoing intervals. Spybot deals with that, but
> it's annoying.

I used this one for about a year and it's fairly easy to setup and
seems to work well. In my case it was for a private site that was only
used by our family so I don't think there was ever more than one or
two connections at a time.

Ultimately the service was replaced on my PC by an older PC retasked
as a server running Linux with web, ftp, file server functions, etc.

Tim

2005\08\12@094818 by John Nall

picon face
> Anyone like to recommend a (preferably free) FTP server for Windows.
Being able to read and write files remotely is about > the extent of my
spec. Anything else is icing.

I have very successfully used PSFTP which is part of a package of
several programs available at
http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html.

The package is free, and a breeze to use (provided that you don't mind
using the command-line feature of Windows).  SFTP is highly recommended
over FTP for transferring files, because of  the security issue.

John



2005\08\12@131421 by Christopher Head

picon face
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Hi,
I agree with the few people who have suggested an SFTP instead of FTP
system. However, if you must use FTP, I've used GuildFTPD before without
seeming to run into any problems. It's free and has a graphical
configuration and monitoring system, and I think it runs even on older
Windowses (eg 98).

Chris
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.1 (MingW32)

iD8DBQFC/Njr6ZGQ8LKA8nwRAmr6AJ90/wbPgfxiGDQZwWvhQt7QIPGz6QCeIL7D
Wxo5+b/9JnkKwumHZEDvEis=
=yj8e
-----END PGP SIGNATURE-----

2005\08\12@140133 by James Newtons Massmind

face picon face
I very much do NOT recommend war ftp.

Why?

- the code is closed source and written by ONE person not a company.

- Because the author is a self reported cracker, dissonant, and political
hotspot.

Other than that, it works just great, as far as I could tell when my company
made me use it anyway.

---
James.



> {Original Message removed}

2005\08\13@001009 by Andrew Warren

face
flavicon
face
Russell McMahon <.....piclistKILLspamspam.....MIT.EDU> wrote:

> Anyone like to recommend a (preferably free) FTP server for Windows.

   I like Filezilla Server.  You can download it (and/or the Filezilla
   FTP client) from:

       http://sourceforge.net/projects/filezilla/

> While I'm here, thoughts on a suitable (again preferably free) Windows
> based POP3 server?

   Mercury Mail, by David Harris (author of the excellent Pegasus Mail
   client that I've been using for the last twelve years):

       http://www.pmail.com

   -Andy

=== Andrew Warren - EraseMEfastfwdspam_OUTspamTakeThisOuTix.netcom.com

2005\08\15@010311 by liam .

picon face
> > Anyone like to recommend a (preferably free) FTP server for Windows.
>
>

Depending upon which version you choose I would recomend most of the
software avaliable from Pablo Software Solutions (I havent used it
all).

http://www.pablosoftwaresolutions.com/html/downloads.html

I have no offiliation with this software but have used some of it many
times due to its size and simplicity (and lack of installation
required on secured systems).

2005\08\15@080009 by Eduardo Garcia

flavicon
face
Hi Russel!
When you say about ftp server the first thing that come in my mind is
FileZilla! This FREE software can be found in sourceforge web site. I have
tried a lot of softwares and this is the best in my view!

Good Luck!


{Original Message removed}

2005\08\15@092511 by Gerhard Fiedler

picon face
Russell McMahon wrote:

> Anyone like to recommend a (preferably free) FTP server for Windows.

I guess you are aware that ftp is a pain for firewall configuration --
either on the server side (passive ftp) or on the client side (active ftp).

Most ftp connections these days are probably passive, because of the easier
client configuration, and because in many connection configurations active
ftp just doesn't work. But it puts the burden of adequate handling of the
(almost) arbitrary connection ports for data connections on the server
side.

The easiest way around this is IMO a router that has a built-in VPN server.
Allows you to connect from a remote location to your local LAN, and most
firewall/safety issues are out of the way. You still can use an ftp server
then to transfer the files, but you don't have to worry so much about
firewall configuration, as the ftp traffic is protected by the VPN
connection.

Gerhard

2005\08\15@094047 by John Remington

picon face
On 8/15/05, liam . <liaaam2spamspam_OUTgmail.com> wrote:
> > > Anyone like to recommend a (preferably free) FTP server for Windows.
> >
> >
>
> Depending upon which version you choose I would recomend most of the
> software avaliable from Pablo Software Solutions (I havent used it
> all).
>
> www.pablosoftwaresolutions.com/html/downloads.html
>
> I have no offiliation with this software but have used some of it many
> times due to its size and simplicity (and lack of installation
> required on secured systems).
>


I second Pablo's FTP, works good.   I' use filezilla and ws_ftp for
client applications, and Pablo's FTP for the server applicaion.  Works
good, easy to install and use, I'm running it on a win95 box along
with apache, php, and mysql..

2005\08\15@202504 by Nino Benci

flavicon
picon face
part 1 612 bytes content-type:text/plain; charset=ISO-8859-1; format=flowed (decoded 7bit)

I use FileZilla. Goto SourceForge.net.

liam . wrote:
{Quote hidden}


part 2 373 bytes content-type:text/x-vcard; charset=utf-8; name=Nino.Benci.vcf
(decoded 7bit)

begin:vcard
fn:Antonio L. Benci
n:Benci;Antonio L.
org:Monash University;School of Physics
adr:;;;Monash University;VIC;3800;Australia
email;internet:@spam@electronic.servicesKILLspamspamspme.monash.edu.au
title:Professional Officer
tel;work:+613 9905 3649
tel;fax:+613 9905 3637
x-mozilla-html:FALSE
url:http://spme.monash.edu.au
version:2.1
end:vcard



part 3 35 bytes content-type:text/plain; charset="us-ascii"
(decoded 7bit)


'[EE]:: [TECHO] The Air Car - zero pollution and ve'
2007\03\20@083803 by Russell McMahon
face
flavicon
face
Matthew McMahon says -

Subject: The Air Car - zero pollution and very low running costs -
gizmag Article


> http://gizmag.com/go/7000/

French designed. Indian made.
300 km range claimed.
Approx 10% of petrol running costs claimed.
E1.5 per 300 km fill.
68 mph toppppp speed.
Lessee.
E1.5 ~~= $US2? ~= $NZ3.
Approx 2 litres petrol at NZ prices.
So 150 km/litre or about 375 mpg-US or 425 mpg imperial.

No mention of pressure used.
90 m^3 of gas said to be stored.
You'd be (very) lucky to get 1 m^3 of storage in a small car so that's
90+ atmosphere =~~ 1500 psi or 9 MPa.
Probably double that.
Would need a very many stage expansion motor to handle that
efficiently.

Very very (very ...) roughly using expanded energy equivalent, 90 m^3
at 1 atmosphere = 90 m^3 x 100 kPa  = 9 MPa energy.
9 E6  /1000 kW/W  /3600 hr/sec = 2.5 kWH = about 10% of what I
calculate the cost would buy in energy equivalent electricity. And 2.5
kWh is utterly insufficient for the task as 20 kWH (see below) is
rather skimpy. Possibly a missed decimal somewhere in my figures but
... .

>From an electricity point of view. $NZ3 buys about 20 kWH of
electricity or the same energy content as 2 litre of petrol.
150 km on a litre of petrol given equivalent energy content is "rather
good".

I very strongly suspect that their energy costing claims are
fallacious.
I'd be happy to be proven wrong.

E&OE as always



       Russell











2007\03\20@092954 by Michael Rigby-Jones

picon face


>-----Original Message-----
>From: KILLspampiclist-bouncesKILLspamspammit.edu [RemoveMEpiclist-bouncesTakeThisOuTspammit.edu]
>On Behalf Of Russell McMahon
>Sent: 20 March 2007 12:38
>To: PIC List
>Subject: [EE]:: [TECHO] The Air Car - zero pollution and very
>low running costs- gizmag Article
>
>Very very (very ...) roughly using expanded energy equivalent, 90 m^3
>at 1 atmosphere = 90 m^3 x 100 kPa  = 9 MPa energy.
>9 E6  /1000 kW/W  /3600 hr/sec = 2.5 kWH = about 10% of what I
>calculate the cost would buy in energy equivalent electricity. And 2.5
>kWh is utterly insufficient for the task as 20 kWH (see below) is
>rather skimpy. Possibly a missed decimal somewhere in my figures but
>... .

http://www.theaircar.com/faq.html#p7 suggests a pressure of 300bar in the tanks.  Then they emphasise safety by saying it's the same type of tank used for LPG storage in busses.  Hmm, IIRC LPG vapour pressure is about 12bar at nominal 25C temperature...

Some interesting stuff on the engine on that website however, especialy the atriculated con rod linkage.  It's only a two stage engine though.

Regards

Mike

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2007\03\20@093721 by Tamas Rudnai

face picon face
In the '70s, '80s maybe lots of airplane modellers used compressed CO2
engines. The biggest problem was that the pipes had frozen up very often. I
suppose when the weather is nice and warm it is not a problem, but what car
would they use in Iceland? :-)

In the other hand I can use the air compressor at the petrol station free of
charge, so it's not so bad idea to use them until they found out what's
going on :-)

Tamas




On 3/20/07, Russell McMahon <spamBeGoneapptechspamBeGonespamparadise.net.nz> wrote:
{Quote hidden}

> -

2007\03\20@094838 by Alan B. Pearce

face picon face
> http://www.theaircar.com/faq.html#p7 suggests a pressure of
>300bar in the tanks.  Then they emphasise safety by saying it's
>the same type of tank used for LPG storage in busses.  Hmm,
>IIRC LPG vapour pressure is about 12bar at nominal 25C temperature...

300 bar is probably similar to that run in compressed air locos used in
hazardous environments around factories and in mines. Don't know if they are
still used now diesel and battery locos are available, but they were
certainly a viable alternative to steam locos.

See http://www.internationalsteam.co.uk/trains/fireless01.htm for examples -
essentially a steam loco with compressed air tank instead of boiler.

2007\03\20@095807 by William Couture

face picon face
On 3/20/07, Alan B. Pearce <TakeThisOuTA.B.PearceEraseMEspamspam_OUTrl.ac.uk> wrote:

> > http://www.theaircar.com/faq.html#p7 suggests a pressure of
> >300bar in the tanks.  Then they emphasise safety by saying it's
> >the same type of tank used for LPG storage in busses.  Hmm,
> >IIRC LPG vapour pressure is about 12bar at nominal 25C temperature...
>
> 300 bar is probably similar to that run in compressed air locos used in
> hazardous environments around factories and in mines. Don't know if they are
> still used now diesel and battery locos are available, but they were
> certainly a viable alternative to steam locos.
>
> See http://www.internationalsteam.co.uk/trains/fireless01.htm for examples -
> essentially a steam loco with compressed air tank instead of boiler.

300 bar is about 4,350 PSI (pounds per square inch).  Scuba divers routinely
use 3,000 PSI (roughly 200 bar).

Bill

--
Psst...  Hey, you... Buddy...  Want a kitten?  straycatblues.petfinder.org

2007\03\20@100347 by Michael Rigby-Jones

picon face


>-----Original Message-----
>From: RemoveMEpiclist-bouncesspamTakeThisOuTmit.edu [piclist-bouncesEraseMEspam.....mit.edu]
>On Behalf Of William Couture
>Sent: 20 March 2007 13:58
>To: Microcontroller discussion list - Public.
>Subject: Re: [EE]:: [TECHO] The Air Car - zero pollution and
>very lowrunningcosts- gizmag Article
>
>300 bar is about 4,350 PSI (pounds per square inch).  Scuba
>divers routinely use 3,000 PSI (roughly 200 bar).
>

How often do scuba divers have trucks crash into them though :D

Regards

Mike

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information contained in it may be confidential and/or protected by
law. If you are not the intended recipient of this message, you must
not make any use of this information, or copy or show it to any
person. Please contact us immediately to tell us that you have
received this e-mail, and return the original to us. Any use,
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No part of this message can be considered a request for goods or
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2007\03\20@101133 by Russell McMahon

face
flavicon
face
> http://www.theaircar.com/faq.html#p7 suggests a pressure of 300bar
> in the tanks.  Then they emphasise safety by saying it's the same
> type of tank used for LPG storage in busses.  Hmm, IIRC LPG vapour
> pressure is about 12bar at nominal 25C temperature...
>
> Some interesting stuff on the engine on that website however,
> especialy the atriculated con rod linkage.  It's only a two stage
> engine though.


300 bar ~~= 4500 psi / 30 MPa - that's VERY high by almost any
standards. And it would take rather specialist compression equipment
I'd imagine. Plus, only two stage expansion seems rather too little
for such extremes of pressure. That's about 17:1 per stage at full
pressure, declining markedly as pressure drops. The large change in
pressure ratio is also liable to provide interesting challenges.

Overall, a good trick if they can really accomplish it.


       Russell.

2007\03\20@101136 by Russell McMahon

face
flavicon
face
2001. War was beginning ...

Note that the site was last updated in December 2005 :-(.
Most website references are to 2002 or 2001 with the odd one to 2003.
A 2002 page referes to a rollout in the next few months.
It would seem that they haven't achieved their goals.

September 2003 Press release re a London demo

       http://www.motordeaire.com/ing/UKPressrelease.html#Eng

Investors meeting, Nice, April 2005.
Video clips provided of power module and "the prototypes" in
operation.
"The prototypes" in 2005 sounds ominous.

       http://www.theaircar.com/niza05uk.html

Hopefully they are still progressing.

Maybe CATS didn't win after all and all their base actually belong to
somebody else?




       Russell




2007\03\20@162320 by Peter P.

picon face
Tamas Rudnai <tamas.rudnai <at> gmail.com> writes:

> In the '70s, '80s maybe lots of airplane modellers used compressed CO2
> engines. The biggest problem was that the pipes had frozen up very often. I
> suppose when the weather is nice and warm it is not a problem, but what car
> would they use in Iceland?
>
> In the other hand I can use the air compressor at the petrol station free of
> charge, so it's not so bad idea to use them until they found out what's
> going on

The air compressor at the gas station gives at most 12bar. You want 300. A scuba
cylinder filling compressor will do the job but it will have to run for the
whole night to fill a car's tanks.

Peter


2007\03\20@163207 by Peter P.

picon face
Once upon a time torpedos were powered exactly like that afaik. The first lesson
after that was to add alcohool or kerosene and water and to burn it so the heat
of expansion was supplied. And not at 300bars. Afaik to avoid losses one expands
the gas through a machine, not through a simple nozzle, and uses reheating (from
ambient air at least, but better with fuel). I don't know how they calculated
the efficiency on that thing because storing compressed air is quite wasteful
(by losing the heat of compression among other things). However I think that
driving a car that uses torpedo propulsion principles is cool (probably in the
same class as turbine karts - and it could race them too).

Peter P.


2007\03\20@171200 by David VanHorn

picon face
>
>  Afaik to avoid losses one expands
> the gas through a machine, not through a simple nozzle, and uses reheating
> (from
> ambient air at least, but better with fuel). I don't know how they
> calculated
> the efficiency on that thing because storing compressed air is quite
> wasteful
> (by losing the heat of compression among other things).



Subs usually have a fair amount of compressed air handy, if they want to
come back up :)

2007\03\20@173136 by Peter P.

picon face
David VanHorn <dvanhorn <at> microbrix.com> writes:

> >  Afaik to avoid losses one expands
> > the gas through a machine, not through a simple nozzle, and uses reheating
> > (from
> > ambient air at least, but better with fuel). I don't know how they
> > calculated
> > the efficiency on that thing because storing compressed air is quite
> > wasteful
> > (by losing the heat of compression among other things).
>
> Subs usually have a fair amount of compressed air handy, if they want to
> come back up :)

Yes but torpedoes have more burning constraints. Also compressed air plants
waste a lot of heat, unless it is used to heat water or buildings or such. The
higher the pressure the more heat is lost. When the air is expanded then the
heat must be put back in or else everything will freeze solid and efficiency
will be very poor (cold expanded air has significantly lower volume than the
same heated - two to five times less). Worse, the efficiency of making
compressed air is only 12.5%. See here:

 http://www.mntap.umn.edu/energy/82-CompAir.htm

I'm not saying that that car can't do what it says it can do, but if it does
what it says then there is likely a little more to it than 'just' compressed air.

Peter P.


'[EE]:: [TECHO] Armadillo Space Access 07 video'
2007\03\26@212304 by Russell McMahon

face
flavicon
face
Videos of "Real Rocket Ships" of the type that would make
Flash Gordon proud ! :-)

Almost any 'true engineer' and all children (of any age) will find
these inspiring and exciting.

Strangely, they don't seem to include any footage of any of the
crashes along the way :-).

If you have *any* interest in the efforts of the Alternative Space
Community and their efforts to achieve low cost alternative access to
orbit and beyond then try and afford the bandwidth needed to download
these marvellous videos of John Carmack's Armadillo Aerospace's
efforts as they evolve from a dustbin size "lander" hovering in a
carpark to the current awesome prototypes which didn't quite manage to
achieve the NASA 'Lunar Lander' challenge benchmark - next year!
(No rocket ship ever built to date has EVER managed to meet the
requirements of the Lunar Lander challenge - including the original
Lunar Landers. So John's craft have more performance capability than
the original Moon Landers).

Animations show how the present "Quad" design forms the basis for a
vertical half quad module intended to lead to a multi module multi
stage orbit capable craft. (16 half-quads in 1st stage, 4 half-quads
in second stage, one half-quad in 3rd stage.

For me one of the most awe inspiring camera shots is looking down from
the Pixel / Texel lander as they descend from altitude onto NASA's
target landing pad.

The workshop shots showing assembly and how much hardware is involved
are extremely interesting.

The high resolution version is substantially nicer to watch if you can
tolerate the file size.

Visitors - ask to see the video. You won't be disappointed.


       Russell

_________

high bandwidth version (62 megs):
http://media.armadilloaerospace.com/misc/sas07_high.mpg


low bandwidth version (19 megs)
http://media.armadilloaerospace.com/misc/sas07_low.mpg

John Carmack


2007\03\27@192052 by Russell McMahon

face
flavicon
face
Videos of "Real Rocket Ships" of the type that would make
Flash Gordon proud ! :-)

Almost any 'true engineer' and all children (of any age) will find
these inspiring and exciting.

Strangely, they don't seem to include any footage of any of the
crashes along the way :-).

If you have *any* interest in the efforts of the Alternative Space
Community and their efforts to achieve low cost alternative access to
orbit and beyond then try and afford the bandwidth needed to download
these marvellous videos of John Carmack's Armadillo Aerospace's
efforts as they evolve from a dustbin size "lander" hovering in a
carpark to the current awesome prototypes which didn't quite manage to
achieve the NASA 'Lunar Lander' challenge benchmark - next year!
(No rocket ship ever built to date has EVER managed to meet the
requirements of the Lunar Lander challenge - including the original
Lunar Landers. So John's craft have more performance capability than
the original Moon Landers).

Animations show how the present "Quad" design forms the basis for a
vertical half quad module intended to lead to a multi module multi
stage orbit capable craft. (16 half-quads in 1st stage, 4 half-quads
in second stage, one half-quad in 3rd stage.

For me one of the most awe inspiring camera shots is looking down from
the Pixel / Texel lander as they descend from altitude onto NASA's
target landing pad.

The workshop shots showing assembly and how much hardware is involved
are extremely interesting.

The high resolution version is substantially nicer to watch if you can
tolerate the file size.

Visitors - ask to see the video. You won't be disappointed.


       Russell

_________

high bandwidth version (62 megs):
http://media.armadilloaerospace.com/misc/sas07_high.mpg


low bandwidth version (19 megs)
http://media.armadilloaerospace.com/misc/sas07_low.mpg

John Carmack



'[TECHO] [EE] Harvesting energy from noise'
2007\06\30@115019 by Russell McMahon
face
flavicon
face
This is essentially a  micro scale version of eg mechanical automatic
watches which have been around for many decades. Different "vibration"
source- essentially same principle. Could be useful but that's an
extremely low power level (40 uW).


> http://www.edn.com/article/CA6454543.html?industryid=47037&nid=2012


           Vrussell.


2007\06\30@131323 by David VanHorn

picon face
Has a better chance of working than that exercise in electrical
hilarity that I posted on last week..

Seems "energy harvesting" or "scavenging" is the in thing these days.


'[TECHO] [EE] Harvesting energy from noise'
2007\07\01@071834 by Peter Todd
picon face
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On Sun, Jul 01, 2007 at 03:01:38AM +1200, Russell McMahon wrote:
> This is essentially a  micro scale version of eg mechanical automatic
> watches which have been around for many decades. Different "vibration"
> source- essentially same principle. Could be useful but that's an
> extremely low power level (40 uW).

If I've got my units right, that's still a little more than 10x more
power than you can get out of a usual, 10 year, 1uA lithium battery,
3.3uW.

Of course, I'm holding out for widely available radioisotope cells... Or
those fancy direct conversion tritium decay based cells that I've read
about. Directly converting the alpha partical decay into electroncs and
capturing them. Tritium is remarkably non-toxic stuff for a nuclear
material. It dissipates into the environment very quickly, has a very
short biological half-life, and is naturally present in quantities far
higher than we can produce, so the "solution to pollution is dilution"
thing actually works out...

I wonder how much power is my little tritium glowlight dissipating
anyway?

- --
http://petertodd.org
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'[TECH]:: Inflation Deflated - The Big Bang's tough'
2008\07\12@220913 by Apptech
face
flavicon
face
First foot :-).

This is an example of one fairly extreme end of what I
expect we may see in the new [TECH] tag. User opinion will
shape where the boundaries are at the [OT] end of the range
and Bob Blick & users will probably shape what we see at the
[EE] end. I'm all in favour of having [EE] doing justice to
Electrical Engineering with [TECH] accommodating anything
that fails the EE purity test.

Any ongoing deep and philosophical discussions that arise
from material such as this (hard to imagine :-) ) would
probably migrate to [OT].



       Russell McMahon
       13 July 2008 14:07 NZT

______________________

"Inflation deflated? - The big bang's toughest test."

This is a full text transcript of an article in a recent New
Scientist magazine. I assume (possibly incorrectly) that
they are entitled to publish it here.

Summary:  Improving measurement accuracies of variations in
the cosmic microwave background information pose severe
challenges to the current best cosmological universe model.

_____________


While the "inflation" model of the big bang has been for 25
years been the best explanation of how what we see in the
universe came about (inflation posits expansion much faster
than current light-speed very soon after the bb to allow
"communication" of information that we now see that could
not be explained by the present laws of physics) it has had
no real experimental or measurement support and its
predictions matched reality only moderately.

This paper covers recent analyses by Benjamin Wandelt, a
cosmologist at the University of Illinois, that suggest that
measurements of variations in the cosmic microwave
background radiation very badly fail the predictions made by
the inflation model. This conclusion is liable to be firmed
up or falsified in the next few years as measurement
accuracies continue to improve.


http://postbiota.org/pipermail/tt/2008-June/003204.html



       Russell McMahon


2008\07\12@231335 by Apptech

face
flavicon
face
First foot :-).

This is an example of one fairly extreme end of what I
expect we may see in the new [TECH] tag. User opinion will
shape where the boundaries are at the [OT] end of the range
and Bob Blick & users will probably shape what we see at the
[EE] end. I'm all in favour of having [EE] doing justice to
Electrical Engineering with [TECH] accommodating anything
that fails the EE purity test.

Any ongoing deep and philosophical discussions that arise
from material such as this (hard to imagine :-) ) would
probably migrate to [OT].



       Russell McMahon
       13 July 2008 14:07 NZT

______________________

"Inflation deflated? - The big bang's toughest test."

This is a full text transcript of an article in a recent New
Scientist magazine. I assume (possibly incorrectly) that
they are entitled to publish it here.

Summary:  Improving measurement accuracies of variations in
the cosmic microwave background information pose severe
challenges to the current best cosmological universe model.

_____________


While the "inflation" model of the big bang has been for 25
years been the best explanation of how what we see in the
universe came about (inflation posits expansion much faster
than current light-speed very soon after the bb to allow
"communication" of information that we now see that could
not be explained by the present laws of physics) it has had
no real experimental or measurement support and its
predictions matched reality only moderately.

This paper covers recent analyses by Benjamin Wandelt, a
cosmologist at the University of Illinois, that suggest that
measurements of variations in the cosmic microwave
background radiation very badly fail the predictions made by
the inflation model. This conclusion is liable to be firmed
up or falsified in the next few years as measurement
accuracies continue to improve.


http://postbiota.org/pipermail/tt/2008-June/003204.html



       Russell McMahon


'[TECH]:: 10 people killed by new CJD-like disease'
2008\07\13@183554 by Apptech

face
flavicon
face
This story appeared in a recent New Scientist.

Deaths are reported from a previously unknown form of CJD
(human version of prion disease, similar to and in some
cases linked to BSE "mad cow disease"). CJD infection, which
leads to dementia, is almost impossible to diagnose pre
death. Ongoing efforts are being made to diagnose and
prevent it.

Conclusions of source of the infection vary.
As some forms of CJD are "naturally occurring" and can run
in families this may be an entirely inherited genetic
effect.
The link below is one of several which report the story.
This one is notable in that the writer suggests alternative
sources. While he has a personal "axe to grind" (his mother
died from CJD) his points may be worthwhile.

       http://cjdmadcowbaseoct2007.blogspot.com/2008/07/10-people-killed-by-new-cjd-like.html



           Russell


'[TECH]:: TECH membership'
2008\07\14@090445 by Apptech

face
flavicon
face
I'd be interested in knowing how many people

1.    Are receiving TECH tag material automatically.
2.    Have explicitly subscribed to TECH
3.    Have been automatically subscribed but intent to
unsubscribe.

Reply to onlist preferably or to me if you don't want to
de-lurk visibly.

Not the sort of thing we'd probably usually do much of in
TECH but useful for people to see who is present here.



       Russell


2008\07\14@092817 by Carl Denk

flavicon
face
Have explicitly subscribed to TECH

Will have to see how this shakes out. Have previously subscribed only to PIC and EE. Sometimes a thread seems to go on and on with little new info, and probably I have contributed to that :( also. Too much mail, using delete key without reading message, but then again there is detail of use to others, kind of grin and bear (bare (sp)) it.:)

And I am guilty of seeking help on stuff that is now considered off topic (Linux and Windows), where I have exhausted other more pertinent forums and found the solution here. Moderating should be somewhat tolerant, if only occasional  and not abused.

Overall, think the list is good. :)



Apptech wrote:
{Quote hidden}

2008\07\14@095453 by Picbits Sales

flavicon
face
I'm getting it automagically without having to change anything in my Piclist
settings.

I think I've got mine to receive all posts

Dom
{Original Message removed}

2008\07\14@095547 by Bob Ammerman

picon face
I opted in
--- Bob Ammerman

----- Original Message -----
From: "Apptech" <EraseMEapptechspamparadise.net.nz>
To: "PIC List" <RemoveMEPICLISTEraseMEspamEraseMEMIT.EDU>
Sent: Monday, July 14, 2008 9:02 AM
Subject: [TECH]:: TECH membership


{Quote hidden}

> --

2008\07\14@100030 by Roger, in Bangkok

face
flavicon
face
This isn't a trick question is it ... ?  Ya still got me all bamboozled over
that nonsense that OT doesn't stand for On Topic!

Okay, okay I'll slither back into lurch mode now ...

RiB

On Mon, Jul 14, 2008 at 1:02 PM, Apptech <RemoveMEapptechspam_OUTspamKILLspamparadise.net.nz> wrote:

{Quote hidden}

2008\07\14@100641 by Derward Myrick

picon face
Apptech,  I am receiving TECH tag material automatically without doing
amything.

Derward



----- Original Message -----
From: "Apptech" <RemoveMEapptechTakeThisOuTspamspamparadise.net.nz>
To: "PIC List" <EraseMEPICLISTspamspamspamBeGonemit.edu>
Sent: Monday, July 14, 2008 8:02 AM
Subject: [TECH]:: TECH membership


> I'd be interested in knowing how many people
<snip>
>        Russell

<snip>


2008\07\14@101532 by Roger, in Bangkok

face
flavicon
face
DANG Russell!  You mean we been disruptin' all those 'lectrons for naught in
order to opt in?!  Sorry, I forgot to mention that I opted in ... and don't
even think for a nanosecond that I'm gonna unscribledebibble and let ya off
the hook!

RiB

On Mon, Jul 14, 2008 at 2:06 PM, Derward Myrick <RemoveMEwdmyrickKILLspamspamearthlink.net>
wrote:

> Apptech,  I am receiving TECH tag material automatically without doing
> amything.
>
> Derward
>
> ...
>

2008\07\14@102430 by Bob Axtell

face picon face
I plan to subscribe ASAP. Busy.

--Bob

On Mon, Jul 14, 2008 at 6:02 AM, Apptech <apptechSTOPspamspamspam_OUTparadise.net.nz> wrote:

{Quote hidden}

> -

2008\07\14@102844 by Jake Anderson

flavicon
face
I started doing stuff to get it,
forgot my password then ran out of time
but i still seem to be getting it ;->

Derward Myrick wrote:
{Quote hidden}

2008\07\14@103651 by D. Daniel McGlothin

flavicon
face
I "Have explicitly subscribed to TECH".

Daniel

2008\07\14@103756 by Dave Lagzdin

picon face
2008/7/14 Apptech <EraseMEapptechspamEraseMEparadise.net.nz>:

> I'd be interested in knowing how many people
>
> 1.    Are receiving TECH tag material automatically.
> 2.    Have explicitly subscribed to TECH
> 3.    Have been automatically subscribed but intent to
> unsubscribe.
>
>
opted-in, (#2)
D

2008\07\14@105746 by Dwayne Reid

flavicon
face
(2) for me - I had to explicitly subscribe.

dwayne


At 07:02 AM 7/14/2008, Apptech wrote:
{Quote hidden}

--
Dwayne Reid   <@spam@dwayner@spam@spamspam_OUTplanet.eon.net>
Trinity Electronics Systems Ltd    Edmonton, AB, CANADA
(780) 489-3199 voice          (780) 487-6397 fax
http://www.trinity-electronics.com
Custom Electronics Design and Manufacturing

2008\07\14@112447 by James Bendall

flavicon
face
Apptech wrote:
> 1.    Are receiving TECH tag material automatically.

That one!

--
James

2008\07\14@113106 by Don Kovalchik - W8DPK

flavicon
face
I had to opt-in.  Receiving posts just fine now.

Back to lurking . .

--Don--


Apptech wrote:

{Quote hidden}

2008\07\14@115118 by Peter Todd

flavicon
face
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Hash: SHA1

On Tue, Jul 15, 2008 at 01:02:26AM +1200, Apptech wrote:
> I'd be interested in knowing how many people
>
> 1.    Are receiving TECH tag material automatically.
> 2.    Have explicitly subscribed to TECH
> 3.    Have been automatically subscribed but intent to
> unsubscribe.

Have always subscribed to everything, and use my email clients
thread-delete button with abandon... :)

- --
http://petertodd.org 'peter'[:-1]@petertodd.org
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=bE33
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2008\07\14@121701 by Gaston Gagnon

face
flavicon
face
Apptech wrote:
> I'd be interested in knowing how many people
>
> 1.    Are receiving TECH tag material automatically.
> 2.    Have explicitly subscribed to TECH
> 3.    Have been automatically subscribed but intent to
> unsubscribe.
>
>  
I do not know if I would have received TECH automatically because I
immediately explicitly subscribed (#2) when the news was out.
Gaston

2008\07\14@130745 by Bob Barr

flavicon
face
On Tue, 15 Jul 2008 01:02:26 +1200, Apptech wrote:

>I'd be interested in knowing how many people
>
>1.    Are receiving TECH tag material automatically.
>2.    Have explicitly subscribed to TECH
>3.    Have been automatically subscribed but intent to
>unsubscribe.


2. I "Have explicitly subscribed to TECH".

Regards, Bob

2008\07\14@133630 by Yair Mahalalel

flavicon
face
Confirmed infoholic with an Apptech habit. Did nothing to subscribe. The
system knows.

Yair.

On Tue, Jul 15, 2008 at 01:02:26AM +1200, Apptech wrote:
{Quote hidden}

> --

2008\07\14@151023 by Vic Fraenckel

picon face
Carl Denk wrote:
{Quote hidden}

1. Receiving automatically
2. Did NOT subscribe to TECH
3. Will wait and see

Vic

--

*____________________________________________________________________________________________*

*Victor Fraenckel
KC2GUI
windswaytoo ATSIGN gmail DOT com**
*

2008\07\14@155534 by peter green

flavicon
face
>1. Are receiving TECH tag material automatically.
I was set to subscribe to everything and still get everything including
tech.
> 3.    Have been automatically subscribed but intent to
> unsubscribe.
>  
Afiact this only happened if you were previously set to receive
everything. Since afaict TECH is meant to fit somewhere between EE and
OT I would hope that there would be very few if any people in this category.

2008\07\14@161644 by Richard Prosser

picon face
1.    Are receiving TECH tag material automatically.

Went to the website to opt-in and found I didn't have to change anything.

RP


2008/7/15 Apptech <spamBeGoneapptechspamKILLspamparadise.net.nz>:
{Quote hidden}

> -

2008\07\14@172603 by William \Chops\ Westfield

face picon face

On Jul 14, 2008, at 6:02 AM, Apptech wrote:

> I'd be interested in knowing how many people

I am receiving TECH automatically, as a result of never
having turned on ANY filtering.

BillW

2008\07\14@181101 by Heinz Czychun

flavicon
face
Hi to all fellow Techies,

       I explicitly subscribed, not wanting to miss a bit, #2.

TTFN,
Heinz

On 14-Jul-08, at 9:02 AM, Apptech wrote:

> I'd be interested in knowing how many people
>
> 1.    Are receiving TECH tag material automatically.
> 2.    Have explicitly subscribed to TECH
> 3.    Have been automatically subscribed but intent to
> unsubscribe.
>

'[TECH]:: NASA Evaluates Sensor Technology for Futu'
2008\07\14@184806 by Russell

flavicon
face
NASA Evaluates Sensor Technology for Future Aircraft EfficiencyNASA is
evaluating an advanced, fiber optic-based sensing technology that could aid
development of active control of wing shape.

   NASA Evaluates Sensor Technology for Future Aircraft Efficiency


NASA: Sun, 13 Jul 2008 23:00:00 -0500



'[TECH] Software tag needed? <-- Re: EE Change CRC '
2008\07\14@190508 by Apptech

face
flavicon
face
Crosspost.
Change to [TECH] tag
New subject line.

_______________________

I suggest that this discussion should be being held in TECH

as it relates to whether material belongs in TECH or
elsewhere. AND the subject line needs changing.

What say any responses are posted there? I'll
dual post this and with a changed subject line.


> My issue is this:

> An EE doesn't have to deal with TECH: or OT: garbage if he
> doesn't want to.
> The poor SE has no choice. ...


Having carefully read that, my original comment applies.

Core:

{Quote hidden}

I generally agree with your arguments. There may well be
many others who agree. It seems likely that such material
will be migrating out of EE (not my choice except as 1 of N
members). Letting the new arrangement settle down and then
seeing how people feel.

James argued for years that a proliferation of tags would
lead to administrative nightmares AND a demand for still
more tags. He may or may not prove right on the first point.
He seems to be being proven right on the second.



           Russell


'[TECH]:: TECH membership'
2008\07\14@190726 by cdb

flavicon
face
I'm a number 2, quite few people I suspect, agree as well!

Colin

:: I'd be interested in knowing how many people
::
:: 1.    Are receiving TECH tag material automatically.
:: 2.    Have explicitly subscribed to TECH
:: 3.    Have been automatically subscribed but intent to
:: unsubscribe.
--
cdb, .....colinspam_OUTspambtech-online.co.uk on 15/07/2008

Web presence: http://www.btech-online.co.uk  

Hosted by:  http://www.1and1.co.uk/?k_id=7988359

Friendship multiplies the good of life and divides the evil.
Baltasar Gracian





'[TECH] Software tag needed? <-- Re: EE Change CRC '
2008\07\14@194443 by Bob Blick

face
flavicon
face
Random thoughts. How can this be made into one coherent sentence?

If it's embedded related software engineering, it goes in [EE].

Discussions about a Delphi app you are writing to connect to your
embedded processor are definitely [EE] - you are writing a program.

Discussions about Bray's Terminal connecting to your embedded processor
are barely [EE] even though it's an application, but you are solving a
problem related to interfacing the two.

If you are writing a web app that interfaces to hardware you made, it's
[EE] if you are discussing the interfacing part (either hardware or
software).

If you are writing a web app for e-commerce, it's not [EE].

If it's about Visio or backup software, it's not [EE].

Adding a software engineering tag doesn't make sense to me. Non-embedded
software seems [OT] because it's incidental to the piclist - people who
do software engineering that isn't embedded related have other hangouts
for that stuff more suited to it than the piclist.


Cheerful regards,

Bob



On Tue, 15 Jul 2008 11:02:53 +1200, "Apptech" <TakeThisOuTapptech.....spamTakeThisOuTparadise.net.nz>
said:
{Quote hidden}

> --

2008\07\14@204114 by Bob Ammerman

picon face
> Adding a software engineering tag doesn't make sense to me. Non-embedded
> software seems [OT] because it's incidental to the piclist - people who
> do software engineering that isn't embedded related have other hangouts
> for that stuff more suited to it than the piclist.
>
>
> Cheerful regards,
>
> Bob

Sounds more than good to me.

I withdraw my (not really made as such) request for another tag :-)

I just got my dander up when it looked like the peripheral software topics
were going to be treated differently from the peripheral hardware topics.

So I read [EE] as 'embedded engineering', *NOT* 'electrical engineering'

--- Bob Ammerman
RAm Systems

'[TECH]:: TECH membership'
2008\07\14@225510 by Andrew Burchill

picon face
:: 1.    Are receiving TECH tag material automatically.
>

autopilot for me, think I'm receiving all channels anyway.

Andrew Burchill

2008\07\15@030104 by Artem Zezyulinskiy

flavicon
face
I'm receiving it automatically.

Artem

Apptech a écrit :
{Quote hidden}

>

2008\07\15@084449 by Gerhard Fiedler

picon face
Apptech wrote:
> I'd be interested in knowing how many people
>
> 1.    Are receiving TECH tag material automatically.
> 2.    Have explicitly subscribed to TECH
> 3.    Have been automatically subscribed but intent to
> unsubscribe.
>
> Reply to onlist preferably or to me if you don't want to
> de-lurk visibly.
>  
I normally read the piclist through gmane.org, and their account doesn't
seem to receive TECH. So for now I'm without, until I change my habits
and my setup.

FWIW, I notified the person who seems to run gmane.org, but he seems to
have better things to do :)

Gerhard

'[TECH] Software tag needed? <-- Re: EE Change CRC '
2008\07\15@085751 by olin piclist

face picon face
Bob Ammerman wrote:
> So I read [EE] as 'embedded engineering', *NOT* 'electrical
> engineering'

Right, which is why I suggest the name be changed to EMB to avoid this
confusion.  The EE tag is now in its third definition.  Most people looking
at it casually would naturally assume Electrical Engineering, which is now
incorrect.


********************************************************************
Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
(978) 742-9014.  Gold level PIC consultants since 2000.

2008\07\15@092000 by Apptech

face
flavicon
face
> Bob Ammerman wrote:
>> So I read [EE] as 'embedded engineering', *NOT*
>> 'electrical
>> engineering'

> Right, which is why I suggest the name be changed to EMB
> to avoid this
> confusion.  The EE tag is now in its third definition.
> Most people looking
> at it casually would naturally assume Electrical
> Engineering, which is now
> incorrect.

I disagree, not surprisingly :-).
People can read it as embedded engineering if it fits their
paradigms better. Others as electrical engineering. Both
will tend to work OK when most people settle into knowing
what it is generally about. It's hardly rocket science. If
it has PICs it's PIC. If Bob doesn't like it it's TECH.
Sounds easy to me :-).

Slightly more seriously, "embedded engineering" is a
specialist term which may fit the mental filters of people
to whom embedded engineering is more natural than breathing,
BUT the term "electrical engineering" is liable to resonate
with a far wider crowd. If someone is plugging transistors
into a breadboard or soldering things on "vero" / vector /
strip board and want to talk about them then EE is where the
talking belongs. To call that embedded engineering is to
take an elitist approach and suggest that if it hasn't got a
processor in it then it doesn't belong.  Which MAY be what
eg Olin intends, but it's a rather greater jump than I
suspect most minds construed when it was suggested that EE
be "purified".


       Russell

'[TECH] Makemake plutoid'
2008\07\15@093736 by Jinx

face picon face
en.wikipedia.org/wiki/Makemake_%28dwarf_planet%29

Initially known as (136472) 2005 FY9, it was discovered on March 31,
2005 by the team led by Michael Brown, and its discovery was announced
on July 29, 2005. On June 11, 2008, the IAU included Makemake in its
list of potential candidates to be given "plutoid" status, a term for dwarf
planets beyond the orbit of Neptune that would place the object alongside
Pluto and Eris. Makemake was formally classified as a plutoid in July 2008

Its diameter is roughly three-quarters that of Pluto. The designation 2005
FY9 was given to Makemake when the discovery was made public. Before
that, the discovery team used the codename "Easterbunny" for the object
because of the discovery time shortly after Easter

Awww

'[TECH] Re: Printed solar panels'
2008\07\15@100607 by Bob Blick

face
flavicon
face
This belongs in TECH - it's a forward-looking press release for
something you can't do.

Thanks, Bob

On Wed, 16 Jul 2008 01:55:41 +1200, "Jinx" <TakeThisOuTjoecolquittKILLspamspamspamclear.net.nz>
said:
{Quote hidden}

--
http://www.fastmail.fm - Same, same, but different…

'[TECH]:: TECH membership'
2008\07\15@120249 by Paul Hutchinson

picon face
Apptech wrote:
> I'd be interested in knowing how many people
>
> 1.    Are receiving TECH tag material automatically.
> 2.    Have explicitly subscribed to TECH
> 3.    Have been automatically subscribed but intent to
> unsubscribe.
>
> Reply to onlist preferably or to me if you don't want to
> de-lurk visibly.
>  

#2, I explicitly subscribed to TECH

Paul Hutch

2008\07\15@123047 by Alex Harford

face picon face
Missed your original email because,
> #2, I explicitly subscribed to TECH

2008\07\15@125407 by Alan Schnittman

picon face

#2.  Back to lurking...


At 09:02 AM 7/14/2008, you wrote:
>I'd be interested in knowing how many people
>
>1.    Are receiving TECH tag material automatically.
>2.    Have explicitly subscribed to TECH
>3.    Have been automatically subscribed but intent to
>unsubscribe.
>
>Reply to onlist preferably or to me if you don't want to
>de-lurk visibly.
>
>Not the sort of thing we'd probably usually do much of in
>TECH but useful for people to see who is present here.
>
>
>
>        Russell
>

'[TECH] Printed solar panels'
2008\07\15@170254 by William \Chops\ Westfield

face picon face

On Jul 15, 2008, at 6:55 AM, Jinx wrote:

> One other big improvement is that the film is omni-directionally  
> receptive and doesn't need to track the sun.

Claims like this set off alarms in my head.  Regular solar cells, and  
certainly thermal collectors of the "black pipe" variety aren't  
particularly "directional", are they?  And they still benefit from  
tracking...

BillW

'[TECH]:: TECH membership'
2008\07\15@183741 by Howard Winter

face
flavicon
picon face
Russell,

On Tue, 15 Jul 2008 01:02:26 +1200, Apptech wrote:

> I'd be interested in knowing how many people
>
> 1.    Are receiving TECH tag material automatically.
> 2.    Have explicitly subscribed to TECH
> 3.    Have been automatically subscribed but intent to
> unsubscribe.

I didn't even realise a TECH tag had been added until I started to see messages with it!

I suppose I was automatically subscribed.  I've just written a filter to place anything with this tag into the (new) "folder" I've created for it, as I do with each PIClist
tag.

Cheers,


Howard Winter
St.Albans, England


'[TECH] Printed solar panels'
2008\07\15@200923 by Sean Breheny

face picon face
This set off alarms for me, too. The reason why it helps to track the
sun is not because of any directionality of the panel. It is because
you want to maximize the amount of watts per square meter which the
panel receives. The closer you can make the line of sight to the sun
match up with the vector perpendicular to the solar panel surface, the
more light you receive. Think about it from the sun's perspective:
when the panel is way off, the sun would only "see" a thin line, but
when the panel is broadside to the sun, the panel appears as big as it
can get.

Sean


On Tue, Jul 15, 2008 at 5:02 PM, William Chops Westfield <.....westfwspamRemoveMEmac.com> wrote:
{Quote hidden}

> -

2008\07\15@202131 by cdb

flavicon
face
Whilst it does sound 'dodgy' I'm not so sure, here is a link from
yesterdays BBC webpage using a solar film:  
http://news.bbc.co.uk/2/hi/technology/7501476.stm

and I recall the CSIRO tried unsuccessfully to get funds to further
research into a flexible and new way of depositing solar cells onto
material.

Colin

:: This set off alarms for me, too. The reason why it helps to track
:: the
:: sun is not because of any directionality of the panel. It is
:: because
:: you want to maximize the amount of watts per square meter which the
:: panel receives. The closer you can make the line of sight to the
:: sun
:: match up with the vector perpendicular to the solar panel surface,
:: the
:: more light you receive. Think about it from the sun's perspective:
:: when the panel is way off, the sun would only "see" a thin line,
:: but
:: when the panel is broadside to the sun, the panel appears as big
:: as it
:: can get.
--
cdb, RemoveMEcolinspamspamBeGonebtech-online.co.uk on 16/07/2008

Web presence: http://www.btech-online.co.uk  

Hosted by:  http://www.1and1.co.uk/?k_id=7988359

Friendship multiplies the good of life and divides the evil.
Baltasar Gracian





'[TECH] back to the farm was : Printed solar pane'
2008\07\15@205551 by Cedric Chang

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face
I am excited to see solar cells of all persuasions popping up.  I  
want to build that 10 square mile solar farm that converts sun energy  
into hydrogen.   Some barren desert land covered with solar cells or  
solar converters.  Water is piped in to supply the raw materials.  
Oxygen and Hydrogen are produced directly from solar or are produced  
from electricity that was produced from solar.  Oxygen and hydrogen  
are piped out or trucked out to be used for nefarious purposes.  
Flora and fauna live in the shade provided by the solar units.  
Individuals invest in modular solar units that are set up on the  
solar farm land.  Sort of like owning a alt-energy oil well.  Lots of  
owners of the modular units.  I would own the land.

cc

'[TECH] Printed solar panels'
2008\07\15@212244 by Cedric Chang

flavicon
face
Maybe if you used glass with a treated surface in a half-cylinder  
shape that directed the solar energy to edge-mounted solar cells, you  
would get decent efficiency without having to move anything.
cc


{Quote hidden}

2008\07\15@220132 by Jake Anderson

flavicon
face
If the material is cheap enough then it would probably be cheaper and
more reliable to just cover the total area available for your solar farm
rather than trying to put in a bunch of steerable panels.

that makes it "omnidirectional" I spose.

William Chops Westfield wrote:
{Quote hidden}

2008\07\15@220437 by William \Chops\ Westfield

face picon face

On Jul 15, 2008, at 6:22 PM, Cedric Chang wrote:

> Maybe if you used glass with a treated surface in a half-cylinder
> shape that directed the solar energy to edge-mounted solar cells, you
> would get decent efficiency without having to move anything.

You probably get "decent efficiency" with a flat panel pointing  
straight up.  But that's not the same as "maximum efficiency."  
Perhaps the real trick is to get ENOUGH output (efficiency be  
damned), in a "small enough" area, at low enough cost, rather than  
maximal efficiency.  I think you could prove that a flat plate has  
the best efficiency of any non-tracking shape?

BillW

'[TECH] back to the farm was : Printed solar pane'
2008\07\15@222021 by Apptech

face
flavicon
face
> Flora and fauna live in the shade provided by the solar
> units.

People could live in the shade created.

> I would own the land.

Tell us when you've bought it and we'll see how it goes.


           RM

'[TECH] Printed solar panels'
2008\07\16@023000 by Yair Mahalalel

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face
The purpose of tracking is to maximize the output, not per land area,
which is relatively cheap, but for solar cell area. They actually waste
quite a lot of the total incoming energy.

Take for example a system that can track the sun until it's 30 degrees
above the horizon before elements start to overshadow each other. To do
that the elements will have to be spaced in a way that when the sun
crosses the meridian half of the incoming light will fall straight to the
ground (by simple geometry).

If your cells are insensitive enough to the light direction, and cheap
enough to be used in such a way, laying them flat will be the most
efficient configuration, as it captures all of the incoming light.

But this is a big if, of course :-)

Yair.

On Tue, Jul 15, 2008 at 07:04:33PM -0700, William Chops Westfield wrote:
{Quote hidden}

> --

2008\07\16@063542 by Bob Ammerman

picon face
A claim was made these new cheap cells don't need to be aimed.

Well, the point it they are really cheap (much, much cheaper) than standard
cells.

Thus, the claim could probably be worded (but not as nicely for the makers
of the new cells):

"Our cells are so cheap that it is cheaper to double (triple, N x) their
area) than to build them into some sort of aimable array."

It probably costs much more to build the structures/controls for aiming than
to just plaster the entire surface with the new cells and then take the Sun
at whatever angle its at.

Perhaps the best arrangement would be a fixed orientation chosen to maximize
the integral of the luminous flux per unit area over a year. This would be
slanted relative to the ground, so you'd end up with a series of panels
spaced apart as necessary to avoid one shadowing the next at any point in
the year. The slanted panels would probably be a lot easier to keep clean
than panels parallel to the ground.

-- Bob Ammerman
RAm Systems

'[TECH] Led center: articles on led'
2008\07\16@082222 by Nicola Perotto

picon face
A lot of short articles on led.
http://led.linear1.org/

'[TECH] Printed solar panels'
2008\07\16@195930 by Yair Mahalalel

flavicon
face
Fixed arrangement that maximizes the total yearly output of the system
is also what I came up with trying to think how such technology might be
optimally used.

The reason why such hypothetical systems bare little resemblance to
current solar power plants, however, is that photo-Voltaic cells, in any
configuration, still have a very poor efficiency relative to other
technologies.

When optimized over the cost of materials, installation and operation,
cheap, easy to produce, photo-Voltaic arrays seem indeed to be a great
solution, but such optimization fails to take into account one other
resource solar power plants consume in gluttonous amounts - land.

Taking the average solar energy flux to be of the order of 100W per m^2,
a 1GW power station will need 10km^2 if it is 100% efficient. The value
of such vast areas is such that in most places it is the limiting
factor. The technology used to build the field can afford itself to be
quite expensive and cumbersome to install, if it can offset this cost
even by a small advantage in conversion efficiency.

I guess that is the reason why places where large deserts can be found,
like south western USA and Australia, are the main investors in
researching and developing large scale photo-Voltaic installations,
while the fields being built in places like southern Spain all use aimed
parabolic mirrors and steam turbines. It's not just that turbines are an
old and proven technology, it's also that it doesn't seem likely that
their conversion efficiency will face serious competition any time soon.

Cheers,
Yair.

On Wed, Jul 16, 2008 at 06:35:09AM -0400, Bob Ammerman wrote:
{Quote hidden}

> --

'[TECH]:: World's Biggest Tsunami | 1720 feet-tall '
2008\07\17@013027 by Apptech

face
flavicon
face
1958 Tsunami in an Alaskan bay - caused by a very large rockfall from a
great height. These evidently occur regularly - perhaps several per decade.

Highest water damage point was 1720 feet above water surface (!!!).

Survivors' tales (2 boats) make interesting reading. Nobody could be happier
about a snapped anchor chain than Howard Ulrich.



{Original Message removed}

'[TECH] Connecting a TV aerial'
2008\07\17@022354 by Cedric Chang

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face
This aerial requires that you attach 300 ohm flat twin-lead cable.  
You can buy a transformer that converts the 300 ohm impedance to 75  
ohms.  The 75 ohm end of the transformer will have a connector for coax.

Some examples:
hhttp://www.radioshack.com/product/index.jsp?
productId=2062049&cp=&sr=1&origkw=75+300+ohm+transformer&kw=75+300+ohm
+transformer&parentPage=search
http://www.amazon.com/Recoton-V348-300-Ohm-Signal-Combiner/dp/B00006HOJL

300 ohm cable
http://www.radioshack.com/product/index.jsp?
productId=2049618&cp=&sr=1&origkw=300+ohm+cable&kw=300+ohm
+cable&parentPage=search


00000000000000000000000000000000000000000000000000
http://www.mindspring.com/~brucec/fmtrans.htm
Matching



Antennas, transmission lines, and tuner inputs all have  
characteristic impedances. You absolutely MUST match these, or losses  
will occur. Fortunately, there are only two impedances commonly used  
in home equipment: 300 ohm and 75 ohm. Antennas are almost always 300  
ohm, and tuners are becoming almost universally 75 ohm. Older tuners  
had two screws for 300 ohm, however. The flat wire with two  
conductors separated by about 3/8 inch is 300 ohm. Cable TV wire is  
75 ohm.

If you have a 300 ohm antenna, 300 ohm lead-in wire, and a 300 ohm  
input on your tuner, you can just hook it all up directly, and the  
only losses you will have are the losses in the wire. The trade-off  
here is that the wire will tend to pick up interference (and stations  
out of the beamwidth of the antenna). If noise and / or interference  
is a problem, you are going to have to use sheilded lead-in. 300 ohm  
sheilded lead in was available in past years, but I don't know if it  
can be found now. This means you are going to have to consider the  
use of 75 ohm cable, and inserting two matching transformers into the  
"chain" - one at the antenna and one at the receiver.



If you have a 300 ohm antenna, and 75 ohm tuner, you must use at  
least one matching transformer. You might as well take advantage of  
75 ohm cable in the process. It has lower losses than 300 ohm  
twinlead, and has better performance when it gets wet. There is  
little to be gained by using 300 ohm twinlead from the antenna to the  
tuner, and converting it at the back of the tuner.



2008\07\17@024244 by Cedric Chang

flavicon
face
Here is an example of a 300 ohm antenna
http://www.radioshack.com/product/index.jsp?
productId=2103085&cp=&sr=1&origkw=300+ohm+antenna&kw=300+ohm
+antenna&parentPage=search

300 ohm antennas are designed to match the impedance of free space  
which is ~ 376.730313 ohms .
Here is more than you will ever want to know about free space impedance.
http://en.wikipedia.org/wiki/Impedance_of_free_space


cc

2008\07\17@090213 by Harold Hallikainen

face
flavicon
face
Speaking of the impedance of free space, I wrote an article on shielding
that used the concept back in 1991. See
http://www.hallikainen.org/rw/insite/ and
http://www.hallikainen.org/rw/insite/WaveZ.pdf .

Harold

--
FCC Rules Updated Daily at http://www.hallikainen.com - Advertising
opportunities available!

2008\07\17@105859 by Don Kovalchik - W8DPK

flavicon
face
The 300 ohm twinlead has much lower loss than the 75 ohm coaxial cable,
especially at UHF frequencies.

For example, at 500 Mhz (US TV Channel 19), good quality 75 ohm coax has
a loss
of about 7 dB/100 ft, whereas 300 ohm twinlead has a loss of about 3 dB
/ 100 ft.
At higher frequencies the difference is even more pronounced.

Properly installed twinlead can perform very well.  In very weak signal
areas
it can make a huge improvement in picture quality. For proper operation,
the
twinlead must be kept away from nearby conductive objects.

However, if the signal strength is adequate, the extra loss of the coax
can be
tolerated and the advantages of coax makes a much simpler installation.

--Don--

Cedric Chang wrote:

{Quote hidden}

2008\07\17@112229 by Sean Breheny

face picon face
I deleted the message so I don't remember who said it but someone
commented that TV antennas have an impedance of 300 ohms because it is
close to the free-space impedance. I don't think this is quite true.
They are 300 ohms because the driven elements are usually some kind of
folded dipoles. I suspect that this is to make them an easy match to
balanced transmission line, which is cheaper than coax and can be less
lossy.

Of course there is a relationship between antenna feedpoint impedance
and free space impedance. However, it is not the case that an antenna
will work "better" if its feedpoint impedance is closer to the free
space characteristic impedance.

Sean


On Thu, Jul 17, 2008 at 11:00 AM, Don Kovalchik - W8DPK <TakeThisOuTw8dpkspamspamarrl.net> wrote:
{Quote hidden}

> -

'[TECH] Canon HF100 camcorder (was: [EE] SDHC Cards'
2008\07\17@141947 by M. Adam Davis

face picon face
On 7/17/08, Bob Ammerman <rammermanEraseMEspamverizon.net> wrote:
> > They are primarily being positioned as the next stage in digital video
> > media.  I just purchased a Canon HF100.....
>
> My son wants to buy that model. Could I ask you your opinion of it?

Changed the topic and subject.  Wonder if this might be OT?  Please
change into soft slippers if you're going to boot me Russell...  ;-D

I've only had it for a few days now, and haven't done any significant
shooting or post processing with it, so you might consider asking me
again in a month or two - I'm taking it on a vacation next week.

I spent a lot of time on here:
http://www.camcorderinfo.com/ratings.php#

which appears to be (or aspires to be) the dpreview of camcorders.
The reviews are fairly thorough.  I also spent some time on amazon.com
reviews and this one had the least number of bad reviews, though it's
a fairly new model.  Lot's of, "I bought X but didn't like such and
such about it, so I returned it and bought this one and it's perfect!"
type reviews.

Noting that I've never owned a camcorder before, here are my first impressions:
- It's small and light - I can see myself using it for long periods
of time without becoming sore, and the case I purchased for it is
smaller than my DSLR case (Canon XTi 400D) so I won't hesitate to
bring it if I think it might be useful wherever I'm going.  Of course,
I'm now faced with the perpetual quandry - which one do I bring, and
if both to I get a larger case for both or let them hang off my
shoulders as two seperate bags?  I think that I could modify an arm
lamp to act as a mount for this - it weighs less than the flourescent
head of the lamp, which could have interesting uses for electronic
documentation.
- It's surprisingly stable - I can't hold a webcam by hand with
noticably annoying shake, but this wasn't annoying.  The lens
stabilisation (vs electronic image stabilisation) gets high marks from
most reviewers, so I think Canon made a good choice here.  I can zoom
in all the way (12x) and while the shake is noticable, the video is
still watchable/usable.  This is freestanding hand shake - when I rest
my elbows on a table or other surface even zoomed in it appears rock
stable.  I was expecting it to be pretty bad given its low mass.
- The macro focus is AWESOME.  I was surprised to find that zoomed
out it would focus to about an inch in front of the lens, which is
perfect for some of the electronics related video I want to capture.
Looking at the fibers in a piece of cloth with perfect focus on a
large high resolution monitor was very nice.
- The image quality is very, very good.  Connected to a full
resolution monitor there's no noticable blurriness, aliasing, or image
compression artifacts.  (well, that I notice on my cheap 24" screen,
anyway)
- Low light performance is good, though I'm told there are better
(including the previous canon SD cameras with larger sensors).  Indoor
use with flourescent or incandescent lighting is fine, although you
can see a marked improvement when the scene is well lit.
- The zoom is variable and starts off very slowly, so it's very smooth
- The camcorder uses a USB profile that is built into Windows Vista,
so even if you use Vista 64 you aren't scrambling around for drivers.
- The lens is threaded so you can add polarizing and other filters
and attachments (telephoto, wide angle, etc) easily and inexpensively.
- Focus is fast.  Unless you are outside the focus range (19" zoomed
in, 1" zoomed out) then hunting was unnoticable or, in low light, not
bothersome.  It has a seperate focus sensor, so a quick pan from a
near object to a far object was spookily in focus by the time I
stopped on the far object.
- The important controls (zoom, start, stop, power) are within hand's
reach for the gripping hand and usable without loosening your grip.

Cons:
- It doesn't do live video via USB, so if you want to use it in live
video situations (webcam, ustream, etc) then you need to have a video
input on your computer, such as composite, or the new HD component or
HDMI capture cards now out.
- Rather than turning the power savings due to solid state recording
into longer record times, they shrunk the battery so it fits inside
the envelope of the camcorder.  The included battery is 7.4v @
~800mAH, and is supposed to last typically just under an hour.
Batteries are not inexpensive, but you can get an extended battery,
and my plan is to simply keep another battery or two around and a
seperate charger - this has worked well with my dslr camera usage
patterns, so we'll see.  Alternately I'm mulling over the idea of an
external battery pack that mounts onto the camera's 1/4" tripod mount
- just a small box that adds 1/2 to 3/4 inch to the height and is
packed with lipoly batteries.  Should be cheaper than an official
canon battery, and would add several hours of time with not much
weight.
- It appears that nearly every camcorder has a built in microphone
that picks up environmental noise too easily, and isn't directional.
This is no exception - I have a relatively noisy office (a fan,
several computers, furnace in next room, etc) and it was very
noticable on a recording of someone speaking quietly.  The reviewers
don't seem to dock points for it, so perhaps it's just par for the
course in camcorder land.
- Very few buttons.  It's a reasonably complex and adjustable
camcorder, but you have to go through more than 1-2 button presses to
alter the exposure, adjust focus manually, aperature, etc.  I don't
know that I'll be using these things much, so it suits me, but I know
some people like to have everything at their fingertips without taking
their eyes off the monitor.
- It doesn't come with an off-board battery charger.  The power
adaptor plugs into the back of the camera while the battery charges
installed in the camera.  I suppose this is how most camcorders work,
but I think I would rather carry around a few batteries and an off
camera charger.  On the plus side, if there's AC nearby you don't have
to worry about the battery running low.
- I could be mistaken, but it appears the camcorder requires that AC
be plugged in when connected to the computer.  Seems odd and somewhat
limiting, but it may be that I was connecting in an odd mode or
something.

None of the cons really bother me, they're just things I would like
out of a perfect camcorder.

Lastly, the price is very nice - you can get this HD camcorder for
just over $600 now.  I purchased the camcorder and two 8GB cards for
under $700 including shipping.

The only thing I wish I could add to this review is comments on the
included software bundle (which processes, converts, and burns DVDs
among other things).  I haven't tried it yet, and I'm concerned that
even though I've got a reasonably nice computer that should actually
do very well for video, I might still see long conversion times.
AVCHD is a relatively new format, so support is limited and sparse in
most video editing programs, so this is an important part of the
bundle.  I'll let you know what I find soon.

Let me know if you have any specific questions about it.

-Adam

--
EARTH DAY 2008
Tuesday April 22
Save Money * Save Oil * Save Lives * Save the Planet
http://www.driveslowly.org

'[TECH]:: AIDs in Africa - three Scenarios to 2025'
2008\07\19@085502 by Apptech

face
flavicon
face
Consider this a trial post of sorts.
I dithered over whether to use OT or TECH.
In some ways it's highly OT, and it's not about technology
in the mechanical sense, but it is very very much about the
use of science and technology to perform vast acts of human
engineering - both medical and social.

As we are learning where people want the TECH boundaries set
I'd be interested in people's comments on the
appropriateness of this in TECH. A shame to noise up the
list with many polls so if you just want to offer an opinion
one way or other please email me offlist - say at above
address or        RemoveMEapptechnzEraseMEspamspam_OUTgmail.com . Please use above
subject line.

By all means comment on list if you feel it's worth doing
so. eg - 'TECH relevant because xxx' OR 'definitely OT as
yyy'. Or whatever. Even "has no place on the list at all"
etc.

__________________

SO

AIDs in Africa - three Scenarios to 2025

   http://www.unaids.org/unaids_resources/images/AIDSScenarios/AIDS-scenarios-2025_report_en.pdf

Interesting, large (220 page), colourful, informative,
stunning, sad UN report on 3 scenarios for AIDs in Africa
until 2025. Published January 2005.
Some photos. Many graphs and tables and maps. Highly
readable.

Far far far more than just an analysis and commentary.
Covers all aspects of life, all factors. Very much a human
interest document. Its approach would be very much condemned
by some.

Some lovely photos that I would have loved to have the
opportunity to take.

Some of the graphs contain information of such enormity that
it's hard to take in at first glance. I found myself doing
calculations in some cases to check that the results I was
seeing could really be per year and not cumulative.

I'm am, of course, well aware of the moral aspects of this
subject.



       Russell












2008\07\19@092010 by Carl Denk

flavicon
face
"has no place on the list at all" Sounds like a medical/social forum would be appropriate. I look at [OT} as not fitting other topics, but of similar nature, i.e. engineering (there are other specialties of engineering beside electrical, and originally there was only Civil and Military), and electronics. Don't need more traffic on a wider subject matter. Probably [OT} is mainly for a subject that starts on one of the other subjects, and wanders off course (which commonly happens) and at that point the last post on the original subject should indicate it's going to [OT} with a new subject header.



Apptech wrote:
{Quote hidden}

2008\07\19@165727 by Richard Seriani, Sr.

picon face
This belongs on some sociology newsgroup or your private blog, definitely
not here on PIClist.


----- Original Message -----
From: "Apptech" <EraseMEapptechspam@spam@paradise.net.nz>
To: "PIC List" <@spam@PICLISTspam_OUTspam.....MIT.EDU>
Sent: Saturday, July 19, 2008 8:54 AM
Subject: [TECH]:: AIDs in Africa - three Scenarios to 2025


{Quote hidden}

> --

2008\07\20@051652 by cdb

flavicon
face
I believe this becomes Tech once an electronic or mechanical gadget /
process becomes apparent. Might be Tech or OT if a superduper
programming algorithm is published that can crunch a billion smaples
per second and the results used for medical or drug research.

As a general discussion though, not relevant to the Piclist.

Colin

:::: Consider this a trial post of sorts.
:::: I dithered over whether to use OT or TECH.
:::: In some ways it's highly OT, and it's not about technology
:::: in the mechanical sense, but it is very very much about the
:::: use of science and technology to perform vast acts of human
:::: engineering - both medical and social.
--
cdb, colinspamBeGonespambtech-online.co.uk on 20/07/2008

Web presence: http://www.btech-online.co.uk  

Hosted by:  http://www.1and1.co.uk/?k_id=7988359

Friendship multiplies the good of life and divides the evil.
Baltasar Gracian





2008\07\20@055330 by Richard Prosser

picon face
Hi Russell,
I'd rate this one as OT. To me, TECH should have a more
electronic-technical content.

I can see the TECH angle - I just don't think it belongs.

I don't have a problem with it being OT.

Richard P

2008/7/20 cdb <RemoveMEcolin@spam@spamspamBeGonebtech-online.co.uk>:
{Quote hidden}

> -

2008\07\20@070842 by Yair Mahalalel

flavicon
face
I think this post fits TECH well, as science and its fruits are major
tools in tackling the problem it presents. The historical, political and
ethical parts are indeed more OTish, but on the other hand I think EE
tech (e.g. cellular communications) will play a leading role in shaping
the next 20 years in Africa, so TECH is reasonable place in the middle.

As for whether this belong in the list on the first place, I think
everything belongs on the list as long as there are people who want to
discuss it and it isn't explicitly offensive to anyone. Neither
bandwidth nor lack of interest are offences, not when a message takes
less than a millisecond to be sent and a thread can be killed with not
much more. People who find it difficult to handle the bandwidth would do
better to revise their toolset than to try and limit it at the source.

That this post yielded no on-topic replies is, of course, a different
matter. :-)

Cheers,
Yair.


On Sun, Jul 20, 2008 at 12:54:37AM +1200, Apptech wrote:
{Quote hidden}

> --

'[TECH]:: Why most published research findings are '
2008\07\20@225105 by Apptech

face
flavicon
face
The claim that 'most published research findings are false',
while demonstrably true, is so utterly contrary to intuition
and to what we think we know about research methods,
statistical analysis and more as to be rejected out of hand
by many.

This sounds like an April fools hoax or similar - it's not.

           Most published research findings are false.

This subject, and the report that it is based on, is of
crucial importance to any engineers or scientists or others
who are interested in understanding how accurate or
believable the results of well conducted and apparently well
conducted research may be and how much they can be depended
on to reflect actual reality. It can be and has been shown
that the majority of claims and research results in even top
class peer reviewed journals are in fact incorrect.

In 2005 a seminal analysis with the title "Why most
published research findings are false" was published in
PLoS medicine ( PLoS Medicine (2[8]:e272)  by an
epidemiologist John P. A. Ioannidis (Department of Hygiene
and Epidemiology, University of Ioannina School of Medicine,
Ioannina, Greece, and Institute for Clinical Research and
Health Policy Studies, Department of Medicine, Tufts-New
England Medical Center, Tufts University School of Medicine,
Boston, Massachusetts). This paper (published as an "essay"
was essentially well received by the scientific community
and (AFAIAA) no major attempts have been made to refute it's
claims. I am aware of some subsequent papers which appear to
take exception to its completeness in some areas but what I
have seen seems more an attempt to join the band-wagon than
to destroy it.
I'll write a brief summary here.
This is necessarily a generalisation and to some extend
overdone - better that you get the point and read the report
than "feel safe".

The intent of the following points is well supported by the
original analysis and AFAIK no major claims have been made
to refute them. If you do research, read research papers,
depend on research results etc then you really want to look
into these results. They apply especially in the medical
research field for reasons commented on in ref 1 below,
would probably be equally or more true in softer* or soft*
science areas (cognitive, psychology, theological,
biological general) and still highly applicable if possibly
less severe in the hard science areas.
[[My rough definitions: Soft - human mind, behavioural,
mental etc. Softer biological and living systems. Hard:
Depend on core 'laws of physics'.]][[No denigration
intended - just trying to scope applicability]].

- Based both on actual analysis of results AND studies of
how results are arrived at MOST published  research results
are false.
- Small studies are more liable to be false.
- Even small studies with excellent statistical support are
liable to be false.
- When many studies are done in a field the chances of false
results being produced grows until it becomes almost certain
that every major hypothesis is covered by reports claiming
it's truth.
- Journals tend to accept papers "going against the flow"
only when they make large and grand contrary claims.
- Better results are obtained by very large studies, by many
coordinated but independent studies of the same basic
premise and using the same premises and approaches.
- Studies which study another researcher's hypothesis are
more liable to be correct than those which study the
researchers own hypothesis.
- All the factors and more that one may suggest may cause
inaccuracies do, and more. Attributions of the effect of
perceived bias on results tends to often enough prove true.

Corollaries from the original report:

Corollary 1: The smaller the studies conducted in a
scientific field, the less likely the research findings are
to be true.
Corollary 2: The smaller the effect sizes in a scientific
field, the less likely the research findings are to be true.
Corollary 3: The greater the number and the lesser the
selection of tested relationships in a scientific field, the
less likely the research findings are to be true.
Corollary 4: The greater the flexibility in designs,
definitions, outcomes, and analytical modes in a scientific
field, the less likely the research findings are to be true.
Corollary 5: The greater the financial and other interests
and prejudices in a scientific field, the less likely the
research findings are to be true.
Corollary 6: The hotter a scientific field (with more
scientific teams involved), the less likely the research
findings are to be true.



1.    While the paper (ref 2 below) is not too too complex
mathematically and is moderately easy to read, it's not as
clear to the layman as it could be. A good starting
commentary can be seen at

*** READ THIS COMMENT FIRST ***

   http://www.marginalrevolution.com/marginalrevolution/2005/09/why_most_publis.html

2.    The original paper is (gratifyingly) available for
free online under a creative commons licence.
Two versions at

   Better formatting:
   http://medicine.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pmed.0020124&ct=1

       http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1182327

3.
http://sci.tech-archive.net/Archive/sci.bio.evolution/2005-09/msg00376.html

Ioannidis has previously identified statistical and
experimental design
problems based on high-throughput techniques such as
microarrays that can
lead to gene-disease predictions being no better than chance
(see the Dec.
20, 2004, issue of The Scientist). He has also followed the
fate of research
findings to quantify their falsification rate, demonstrating
recently, for
example, that five of the six most cited epidemiological
studies since 1990
have already been refuted (JAMA, 294:218-28, 2005).

4. Supporting comments

   http://online.wsj.com/public/article_print/SB118972683557627104.html

Quotes -

"He has done systematic looks at the published literature
and empirically shown us what we know deep inside our
hearts," said Muin Khoury, director of the National Office
of Public Health Genomics at the U.S. Centers for Disease
Control and Prevention. "We need to pay more attention to
the replication of published scientific results."

Quoting Ioannidis

5.    PLoS medicine
PLoS Medicine is a peer-reviewed, international, open-access
journal publishing important original research and analysis
relevant to human health.

       http://medicine.plosjournals.org/perlserv/?request=index-html&issn=1549-1676

6. Various on this result

Wall Street Journal Sep 14, 2007
   http://online.wsj.com/public/article_print/SB118972683557627104.html


7. OK blogs thereon

  http://universalacid.blogspot.com/2005/08/why-most-published-research-findings.html



8.    Wannabees
       ... Sometimes it's OK for results to be wrong ...
       ... more & bigger studies is better ... [[But he
already says that ]]

   http://www.eurekalert.org/pub_releases/2007-02/plos-imp022207.php

9.         Gargoyle sez

       http://www.google.co.nz/search?num=100&hl=en&newwindow=1&safe=off&q=%22JOHN+IOaNNiDIS%22+%22why+most+published+research+findings+are+false%22&meta=




       Russell McMahon


2008\07\21@025321 by cdb

flavicon
face
On Mon, 21 Jul 2008 14:50:15 +1200, Apptech wrote:

:: Corollary 4: The greater the flexibility in designs,
:: definitions, outcomes, and analytical modes in a scientific
:: field, the less likely the research findings are to be true.

well this seems plain logical to me. If you accept that there is no
such thing as absolute certainty, (Heidelberg was it?) then you can
only opt for ' that which seems most likely at the time given the
information available ' . Empirically this would also be seen to be
true, when one considers all the scientific 'facts' that have been
found, only for 8 months later someone else to discover they're
probably wrong, and in all that time a gazillion people around the
world have declared themselves, fitter/better etc.

:: Corollary 5: The greater the financial and other interests
:: and prejudices in a scientific field, the less likely the
:: research findings are to be true.

I think this comes about due to the way funding is provided,
especially for Universities.  Much research is done off the back of
other, so you only need, and error in the original research for it to
be continued through.

As 'them' in charge are more likely to allocate funds only for those
projects that are liklet to succeed or get big headlines, thereby
amassing more money thorugh government grants, I wouldn't be
surprised.

In fact, despite those who will leap in, I don't deride people who
think they may or have discovered things such as Perpetual Motion.

1. it depends on  the definition of PM,
2. every now and then some bright spark changes some of the laws of
maths and physics, so there is no guarantee that one day someone will
a 'have an Einstein' moment, and discover the apparently immutable
laws of physics aren't.

I'd be interest in seeing that paper about TMA's, until recently I
provided equipment and software for researches who use that method.

Colin

--
cdb, .....colinSTOPspamspam@spam@btech-online.co.uk on 21/07/2008

Web presence: http://www.btech-online.co.uk  

Hosted by:  http://www.1and1.co.uk/?k_id=7988359







2008\07\21@032410 by Apptech

face
flavicon
face
> :: Corollary 4: The greater the flexibility in designs,
> :: definitions, outcomes, and analytical modes in a
> scientific
> :: field, the less likely the research findings are to be
> true.


> ...If you accept that there is no such thing as absolute
> certainty, (Heidelberg was it?)

If you pressed me, I'd say no. But who can tell for sure?

I think the point he is making is that increased freedoms in
asking the actual question leads to a greater chance that
the answers are wrong. ie where the method of study and the
definitions and accepted results that define success and
failure are tightly constrained the answers are more likely
to be correct than when the opposite is the case and each
researcher is free to establish their own guidelines.

In one of the other papers I cited (one of the two wannabees
I think) someone suggests that society accepts being fed
incorrect results if the subject is important enough (or was
that unimportant enough?). AFAIR it was 'important enough'
which seems the opposite of what I'd expect. In skimming I
may have missed his point.



       Russell

2008\07\21@051155 by Yair Mahalalel

flavicon
face
Contrary to intuition? We are dealing with ventures into the
qualitatively unknown, of the sort that often are also previously
unimaginable, and you never know when.

And you're applying to it the most flexible and inventive device we've
ever seen, able to generate dozens of hypotheses and ad-hoc models a
minute, and immediately rely and use any of them, if only to save its
life, or its research grants.

And you find it unintuitive they're mostly wrong?

In my line of work there are several methods used to minimize that
effect -

- Data analysis has to quantify all the sources of noise, background
 events and all other possible causes of measurement inaccuracy,
 including how they might combine forces to generate artifacts
 masquerading as new findings.

- The measurement data itself is often inaccessible to the researchers
 until the last moment of the analysis. It is kept in a "locked box"
 until all the software and procedures are in place and only after they
 have been satisfactorily demonstrated on simulation and control data,
 it is run on the real data, to prevent people from optimizing the code and
 trying to "improve their accuracy" after seeing potentially biasing
 results.

- In order to claim a discovery, the researchers must show that the
 chances that the outcome was a results of a statistical fluke is less
 that one in ten million.

- In large experiments the results usually spend another year or so
 undergoing internal scrutiny by other experiment members which are not
 part of the original team. This is usually the harshest step, where
 every impossible scenario is checked. Nobody likes wrong results
 published under his name.

- Peer reviews are another step. No one would like to see you fail more
 than the competition.

- Results of a single experiment are never accepted, no matter how
 convincing they look. That is why on the LHC ring there are two large
 experiments, identical in their requirements, and as different as
 possible in their technology and implementation. And still this is
 considered a sad state of affairs. Originally there was supposed to be
 the SSC with its different energy range, location (and therefore
 mentality), etc.

And we expect to be wrong. What is often perceived as the conservatism
of the scientific establishment has its basis in the exact opposite.
There wouldn't be any point to this job if not to break current theories
and establish new, truer ones. But the human mind being what it is (with
the only thing more susceptible to self-deception being groups of human
minds), exhilarating as any result might be it takes years from initial
publication until it is accepted (and the prizes granted), and only
then, after it has been throughly cross-checked, we might expect to be
wrong only half of the times.

Cheers,
Yair.

On Mon, Jul 21, 2008 at 02:50:15PM +1200, Apptech wrote:
{Quote hidden}

> --

2008\07\21@064822 by Yair Mahalalel

flavicon
face
On Mon, Jul 21, 2008 at 07:20:48PM +1200, Apptech wrote:
>
> In one of the other papers I cited (one of the two wannabees
> I think) someone suggests that society accepts being fed
> incorrect results if the subject is important enough (or was
> that unimportant enough?). AFAIR it was 'important enough'
> which seems the opposite of what I'd expect. In skimming I
> may have missed his point.

It appears to me that indeed society's tolerance to bovine solid waste
is strongly and positively correlated with the importance of the
subject. It is clearly visible even here on the list, where people are
quick to correct others' mistakes when it comes to e.g. component
parameters, but when presented with evidence that the troposphere might
be on the brink of thermal runaway, you'd be hard pressed to find
anyone who will bother to investigate in which direction it might
spiral.

I'd even say that rational discussion is deferred on practically all
topics which are very important - energy, pollution, economic and
social disparity, race and gender inequality, the exponential nature of
technological progress, radical life extension, ownership laws of
information (i.e. subsets of the natural numbers), etc. etc. On most of
these it is almost impossible to even find raw facts which are of decent
quality.

The reason is probably that even though democracy and liberalism have
been quite successful in the past couple of centuries, the basic
instincts of the common man are still those of a slave. We expect to be
lied to when at war, we expect to be lied to when interested parties are
involved (compare medical journals to mathematical, for example), etc.
Often we only discover something to be important by first noticing
the hand waving and verbal acrobatics. Often our first protest isn't in
defence of honesty - we resent when being lied to _needlessly_.

(Admittedly the middle east might be a vantage point that introduces
some bias in itself...)

Cheers,
Yair.

2008\07\21@065039 by Apptech

face
flavicon
face
> Contrary to intuition? ...

> And you find it unintuitive they're mostly wrong?

You don't know me overly well, do you ? :-).
(I have no problem with that, I'm about half a world away).

>> ... while demonstrably true, is so utterly contrary to
>> intuition
>> ... as to be rejected out of hand by many.

The wording was chosen with more care than may be obvious.
I'm trying to slip through mental filters here, not just on
list but also for one chosen BCCee. And in that case there
are several aspects being addressed at once. Important ones
that I want to try and get the subject's "foot in the door"
and not rejected out of hand without thought.

BUT the list was my main audience. It is very easy for
people to throw up their hands in disgust and walk away from
such grandiose and sweeping claims, so a certain amount of
preparation is required before just springing the subject on
the unwary. If I'd just provided a subject line and a web
link it would have taken me much less effort. Hopefully this
way maximises the audience.

Lessons learned from this may/should serve people a
lifetime.

____________

I did / do like your list of checks and balances.

A shame they are not (or, alas, cannot) be applied in a few
other 'sciences' and areas of endeavour that I won't even
name here for risk of starting a conflagration.


       Russell






2008\07\21@065042 by Apptech

face
flavicon
face
{Quote hidden}

It's the Higgs Bo ...
Er.
Um.
Maybe not.
In fact, definitely not.
Just another Boojum.
Oh well ...


       Russell
       (For the Higgs was a Boojum you see*).

__________

* For the perplexed

   http://en.wikipedia.org/wiki/Snark_(Lewis_Carroll)

And, perhaps, " ... threatened its life with a railway share
..." is explained here

       http://en.wikipedia.org/wiki/Railway_Mania







'[TECH] Set pixel for Linux'
2008\07\21@171128 by Herbert Graf

picon face
Hello all,

was wondering if someone could give me some quick advice.

I need to write a quick program, running under Ubuntu. Basically I
simply need a form, and to be able to draw the pixels in the form to
whatever I want.

Speed isn't of utmost concern (obviously faster the better). I would
prefer a solution that uses C/C++ (simply because I have to merge this
project with existing code, don't want to spend too much time porting).

Can anybody point me to a simple example of a program that simply opens
a window and sets a single pixel, I can expand it from there! :)

Quick google searches have presented me with GTK being a possible
solution, but I'll be damned if I can find a SIMPLE example that creates
a form and draws a line or sets a pixel.

Thanks, in advance.

TTYL

'[TECH]:: Why most published research findings are '
2008\07\21@172145 by piclist

flavicon
face
On Mon, 21 Jul 2008, cdb wrote:
> 1. it depends on  the definition of PM,
> 2. every now and then some bright spark changes some of the laws of
> maths and physics, so there is no guarantee that one day someone will
> a 'have an Einstein' moment, and discover the apparently immutable
> laws of physics aren't.

I am not suporised most papers are wrong.  Thats the nature of science,
throwing theories out there and letting them fight to the death. :-)

As far as overturning the laws of physics, for a long time now we have
just been adding more details on to the laws, not overturning them.

The laws of orbital motion are still good enough for Nasa to use in
plotting spacecraft.  Einstien didn't blow the old laws of gravity away..
the results of both theories are nearly identical.  And when the next one
comes along (quantum gravity maybe?) I fully expect it will give results
nearly exactly with Newton as well, just differing at the far end of the
decimal point.

Now.. it's all still just observation and theory, so yes, someone COULD
come up with a theory that turns something major upside down.  But looking
at the progression of science, it seems pretty unlikely.

PS. I would be thrilled and estatic to read that some major physical law
just got proven wrong, as would most every researcher.  I just don't see
it happening.  Kind of like my feelings on winning the lottery.  Would be
nice, but the chances are too low to waste money buying a ticket on. :-)

--
Ian Smith
http://www.ian.org

'[TECH] Set pixel for Linux'
2008\07\21@205349 by M. Adam Davis

face picon face
Direct x-windows (ie, no need to fiddle with finicky toolkits, etc):

http://marvel.incheon.ac.kr/infomation/xwindow/Xwindows%20Programming.htm

Enjoy!

Found via google search, "xwindow C draw pixel example."

The framebuffer is another low-cost way to graphics - essentially
drawing straight to the screen, but I don't know how/if Ubuntu
supports it easily.

-Adam

On 7/21/08, Herbert Graf <hgrafEraseMEspam@spam@email.com> wrote:
{Quote hidden}

> -

2008\07\21@212425 by John La Rooy

flavicon
face
On Tue, Jul 22, 2008 at 7:11 AM, Herbert Graf <RemoveMEhgrafspamspamBeGoneemail.com> wrote:

> Hello all,
>
> was wondering if someone could give me some quick advice.
>
> I need to write a quick program, running under Ubuntu. Basically I
> simply need a form, and to be able to draw the pixels in the form to
> whatever I want.
>
> Speed isn't of utmost concern (obviously faster the better). I would
> prefer a solution that uses C/C++ (simply because I have to merge this
> project with existing code, don't want to spend too much time porting).
>
> Can anybody point me to a simple example of a program that simply opens
> a window and sets a single pixel, I can expand it from there! :)
>
>
Sounds like a gdk job. gdk is the layer below gtk
http://library.gnome.org/devel/gdk/stable/
http://www.gtkmm.org/docs/gtkmm-2.4/docs/tutorial/html/ch15.html

John La Rooy

'[TECH] For all things Aerials'
2008\07\22@065800 by cdb

flavicon
face
Just checking my favourites book, and this came to light.

http://www.cebik.com/edu/edu4.html

All about various antennas and electrical modelling thereof.

To see some of the content you do have to register.

Colin
--
cdb,  on 22/07/2008



'[TECH] Set pixel for Linux'
2008\07\22@075030 by sergio masci

flavicon
face
part 1 1275 bytes content-type:TEXT/PLAIN; charset=US-ASCIIHi Herbert,

I've scraped together some code that should give you the basics of what
you need. It came from a working system so I know it works. If nothing
else it should give you details of what to search the net for. A good book
to look at is "xlib programming manual" ISBN 1-56592-002-3

Regards
Sergio Masci


On Mon, 21 Jul 2008, Herbert Graf wrote:

{Quote hidden}

> --

'[TECH]:: He3 fusion power / Lunar Helium'
2008\07\22@100735 by Apptech

face
flavicon
face
>From an Arocket  post

>> So far we haven't got He3 contained fusion, or indeed any
>> form of contained sustained fusion, and He3 is several
>> steps
>> up the hardness ladder from what we will see initially
>> with
>> contained controlled fusion.

> Why?  Specifically, why is fusing He-3 with H-2 any harder
> than fusing H-3
> with H-2?


Far from my specialist topic. But ...
Coz that's what the experts say.
Higher energy levels.
Hotter.
More ..

Artemis project. Excellent You'll be sorry ...

       http://www.asi.org/adb/02/09/

_____________

       http://en.wikipedia.org/wiki/Helium-3
       http://en.wikipedia.org/wiki/Helium_fusion <- not
much use

Almost useful at low technical level
       http://www.space.com/scienceastronomy/helium3_000630.html

       http://fti.neep.wisc.edu/gallery/pdf/space_com063000.pdf



Slideshow.
You'll be sorry again ...

       http://fti.neep.wisc.edu/neep533/FALL2001/lecture25.pdf

This team has one running.
Efficiency is 'a bit low" [tm]

       http://peakoildebunked.blogspot.com/2006/01/227-helium-3-fusion.html

Y don't buy no ugly slideshow (with many "images removed for
copyright reasons" )
FWIW Says reason Chinese want to do lunar access if for He3
mining.

       http://ocw.mit.edu/NR/rdonlyres/Nuclear-Engineering/22-012Spring-2006/C3E48256-762A-49FF-9B18-1E5A5D39F89B/0/helium3_fusion.pdf


2008\07\22@113543 by Chris Smolinski

flavicon
face
>  >From an Arocket  post
>
>>>  So far we haven't got He3 contained fusion, or indeed any
>>>  form of contained sustained fusion, and He3 is several
>>>  steps
>>>  up the hardness ladder from what we will see initially
>>>  with
>>>  contained controlled fusion.
>
>>  Why?  Specifically, why is fusing He-3 with H-2 any harder
>>  than fusing H-3
>  > with H-2?
>

Fusion in general is "hard". Nature can do it with large masses and
the assistance of gravity working for free. It doesn't seem to scale
down very well to our levels. IMHO I don't think it will.

--

---
Chris Smolinski
Black Cat Systems
http://www.blackcatsystems.com

'[Tech] What to do about compiler bug and source co'
2008\07\22@135114 by William Couture

face picon face
OK, I've run into a situation at work, and would like some feedback from the
community.

I've found a nasty bug in a C compiler (IAR for Atmel (ATMega),
version 4.21A and 5.11B)
(using the ATMega644 and cranking optimization up to max, 32-bit locals that are
put in registers are not properly handled (only sets lower 2 bytes out
of 4, or in one case
does not set registers at all!)).

I'm going to contact IAR shortly, but since I can't reproduce it in a
sample fragment, I'm
sure that IAR will want the entire source.  But, since it has our
propritary code, work
does not want the source to be sent out.

How would you handle this situation?

Thanks,
  Bill

--
Psst... Hey, you... Buddy... Want a kitten? straycatblues.petfinder.org

2008\07\22@143706 by William \Chops\ Westfield

face picon face

On Jul 22, 2008, at 10:45 AM, William Couture wrote:

>
> I'm going to contact IAR shortly, but since I can't reproduce it in  
> a sample fragment, I'm sure that IAR will want the entire source.  
> But, since it has our propritary code, work does not want the  
> source to be sent out.
>
> How would you handle this situation?

1) report the bug without source code.  Perhaps it is a known issue  
Perhaps there is already a fix available.

2) Meanwhile, begin editing your example to make it as small and self-
contained as possible.  manually include headers.  Delete irrelevant  
code.  Etc.  If you can't create a simple non-proprietary example,  
you should be able to at least create a pretty useless fragment  
starting from the proprietary function.

3) In the end, consider that a well-established high-end compiler  
company can probably be trusted with moderate amounts of proprietary  
code.  Make sure that they understand that that's what they're  
getting ("NOT for publication as an example of the bug!") and proceed  
anyway unless the code fragment (from 2) in question REALLY contains  
key confidential intellectual property...

BillW

2008\07\22@144502 by sergio masci

flavicon
face


On Tue, 22 Jul 2008, William Couture wrote:

{Quote hidden}

Strip out as much source code as possible such that the compiler still
produces the bug.

Start off with a copy of the project. Systematically delete the contents
of functions which are unrelated to the function where you are
experiencing the problem (leaving just the empty function). Keep doing
this until the compiler starts behaving, then undo until the compiler
starts misbehaving again. Make a note of which functions are vital to
the bug and then try again with functions you havent touched yet.

You will end up with some functions and globals which are not referenced
anywhere. try removing them completely, a few at a time until the compiler
starts behaving itself again, then undo the changes until the compiler
starts misbehaving again. you should be able to drastically reduce the
code necessary to reliably reproduce bug.

Regards
Sergio Masci

2008\07\22@181738 by Tomás Ó hÉilidhe

picon face


William Couture wrote:
> OK, I've run into a situation at work, and would like some feedback from the
> community.
>
> I've found a nasty bug in a C compiler (IAR for Atmel (ATMega),
> version 4.21A and 5.11B)
> (using the ATMega644 and cranking optimization up to max, 32-bit locals that are
> put in registers are not properly handled (only sets lower 2 bytes out
> of 4, or in one case
> does not set registers at all!)).
>  


I had a program before that worked perfectly on several different
platforms (Windows, Mac, Linux) with several different compilers until I
compiled it with the highest optimiser turned on for a particular
compiler ( -O3 with gcc ). Since the code worked perfectly on so many
different systems up until that point, my initial reaction was that
there must be a bug in the compiler. Anyway, the offending code turned
out to be:

   void StrToLower(char *p)
   {
       while (   *p++ = tolower( (char unsigned)*p )   );
   }

The problem here is that the behaviour is "unspecified" when it comes to
whether "*p++" or "*p" is evaluated first. For some reason, when I upped
the optimisation, "*p" became the expression that was evaluated first.

I'm not saying there's definitely not a bug in the compiler, but I'd
definitely scrutanise the code for sequence point violations and also
for unspecified behaviour. If you forced me to bet my house on what was
the problem, I'd reluctantly have to go with the code.


> I'm going to contact IAR shortly, but since I can't reproduce it in a
> sample fragment, I'm
> sure that IAR will want the entire source.  But, since it has our
> propritary code, work
> does not want the source to be sent out.
>
> How would you handle this situation?


I'd be interested in glancing over the code if you wouldn't mind sending
me a snippet. I'd pay particular attention to lines of code that mention
the same variable name more than once.

'[TECH] Myke Predko and cyber-electronic warfare'
2008\07\22@183336 by Bob Blick

face
flavicon
face
Saw our old PICLIST buddy's name on Slashdot, positing a question to the
Army:

http://interviews.slashdot.org/article.pl?sid=08/07/03/1913245

Cheerful regards,

Bob

--
http://www.fastmail.fm - Faster than the air-speed velocity of an
                         unladen european swallow

'[TECH]:: Why most published research findings are '
2008\07\22@205437 by Cedric Chang

flavicon
face
> ___________
>
> I did / do like your list of checks and balances.
>
> A shame they are not (or, alas, cannot) be applied in a few
> other 'sciences' and areas of endeavour that I won't even
> name here for risk of starting a conflagration.
>
>
>         Russell



Maybe we could mosey on over to the [OT] tag and discuss 'science  
areas' that are truly bogus, such as psychology and psychiatric  
medicine.
cc




'[TECH]:: He3 fusion power / Lunar Helium'
2008\07\22@221555 by Apptech

face
flavicon
face
Of the references I posted on He3 fusion and lunar Helium 3,
this one ( a "slideshow") makes the best compact
presentation of what is hoped for from it.


       http://fti.neep.wisc.edu/neep533/FALL2001/lecture25.pdf



           Russell

'[Tech]Breaking of Mifare algorithm to be published'
2008\07\22@233331 by cdb

flavicon
face
Surprised a certain Moa inhabitant hasn't posted about this. :)

A court in Holland has thrown out a challenge by NXP (a Smartcard
maker) to stop  some Dutch Universities from publishing the hack
concerning how to copy cards contents and travel free using the UK's
London Oyster Card.

As Philips own the Mifare technology, they probably are none too
chuffed at this flaw in one of their chip lines.

This isn't new, those who get  Elektor Magazine and got the free
Mifare Cards, will know that they carried an article about the hacking
of Mifare cards by I think it was Delft University. They've also
published an article concerning the hacking of those nice new chips in
ones passport.  Maybe Wouter can confirm this.

http://news.bbc.co.uk/2/hi/technology/7516869.stm

Colin
--
cdb,  on 23/07/2008



'[Tech] What to do about compiler bug and source co'
2008\07\23@000332 by Richard Prosser

picon face
Bill

Can you just remove the parts of the code that are sensitive and still
replicate the problem? Maybe fill out the gaps with "rubbish" or a big
array/lookup table or something.

RP

2008/7/23 William Couture <spamBeGonebcoutureKILLspamspam@spam@gmail.com>:
{Quote hidden}

> -

2008\07\23@010019 by Vitaliy

flavicon
face
William Couture wrote:
> I'm going to contact IAR shortly, but since I can't reproduce it in a
> sample fragment, I'm
> sure that IAR will want the entire source.  But, since it has our
> propritary code, work
> does not want the source to be sent out.
>
> How would you handle this situation?

How about using GoToMeeting.com or similar, and let IAR compile/test the
code on your machine? This way, they can see exactly what's happening, yet
you don't have to send them a single line of code.


'[TECH]:: Worlds fastest train for olympics - Walke'
2008\07\23@035937 by Apptech

face
flavicon
face
22 July
NewScientistTech

       http://technology.newscientist.com/article/dn14380

The fastest rail service on the planet will begin next
Friday, linking Beijing with one of China's Olympic co-host
cities, nearby Tianjin.

The spacious interiors – more like aircraft cabins than
train carriages – will ferry passengers at speeds reaching
350 kilometres per hour, cutting the current journey time by
1 hour, to 30 minutes. In tests the trains have reached
394kph.

"Its operational speed is the fastest in the world. It's
very comfortable and quiet," said Zhang Shuguang, head of
the Railway Ministry's Transport Bureau. "There's a French
train that has gone 500kph in tests, but only in tests."

___________________

The spokesman, and NewScientistTech, seem to be conveniently
unaware of the 430 kph Train that I used a few weeks ago -
from Shanghai city edge to Shanghai's Pudong airport. Been
running for some years.

Impressive ride. I have videos. 2nd most impressive
impression is the cars on the motorway zipping past
'backwards' at their snail pace 100 kph.

Most impressive impression is passing the other train going
in the other direction. < 1 second to pass.



          Russell






'[Tech] What to do about compiler bug and source co'
2008\07\23@131017 by Martin

face
flavicon
face
Tomás Ó hÉilidhe wrote:

>
> I had a program before that worked perfectly on several different
> platforms (Windows, Mac, Linux) with several different compilers until I
> compiled it with the highest optimiser turned on for a particular
> compiler ( -O3 with gcc ). Since the code worked perfectly on so many
> different systems up until that point, my initial reaction was that
> there must be a bug in the compiler. Anyway, the offending code turned
> out to be:
>
>     void StrToLower(char *p)
>     {
>         while (   *p++ = tolower( (char unsigned)*p )   );
>     }
>
> The problem here is that the behaviour is "unspecified" when it comes to
> whether "*p++" or "*p" is evaluated first. For some reason, when I upped
> the optimisation, "*p" became the expression that was evaluated first.
>

Postfix increment (n++) occurs after the value is used.
i.e:

b=0;
a = b++ + 4;

results in:
b==1
a==4


So I don't understand how it wouldn't be a bug in the compiler. I have
code that does something similar:

while(*p)
{
       foo(*p++);
}

Starts at p[0] - if it were an undefined OOP there should be a major
problem.
-
Martin

2008\07\23@131915 by Herbert Graf

flavicon
face
On Tue, 2008-07-22 at 13:45 -0400, William Couture wrote:
> OK, I've run into a situation at work, and would like some feedback from the
> community.
>
> I've found a nasty bug in a C compiler (IAR for Atmel (ATMega),
> version 4.21A and 5.11B)
> (using the ATMega644 and cranking optimization up to max, 32-bit locals that are
> put in registers are not properly handled (only sets lower 2 bytes out
> of 4, or in one case
> does not set registers at all!)).
>
> I'm going to contact IAR shortly, but since I can't reproduce it in a
> sample fragment, I'm
> sure that IAR will want the entire source.  But, since it has our
> propritary code, work
> does not want the source to be sent out.
>
> How would you handle this situation?

I deal with this sort of thing all the time at work, you have a few
options:

1. Create a test case that doesn't use your proprietary code, but
replicates the problem. You mention you haven't been able to reproduce
it, so it looks like this isn't an option.

2. Get an NDA signed so that your code can go to them. This
unfortunately isn't always acceptable to both sides.

3. Have them give you a "special" build of their compiler with debugging
enabled, and then send them the debug info. Oftentimes this is enough to
figure out what's going on. THEY might not want to give you the debug
enabled version of the compiler.

4. Have them send an FAE to your site (or alternatively have them
remotely log into one of your machines) to debug the issue on your
machine.

5. Find a workaround, note the problem exists and ignore the issue. This
last one REALLY sucks, but sometime legalities make it the only option.

TTYL

2008\07\23@141909 by Tomás Ó hÉilidhe

picon face
Martin wrote:
> Postfix increment (n++) occurs after the value is used.
> i.e:
>
> b=0;
> a = b++ + 4;
>
> results in:
> b==1
> a==4
>  


Indeed.



{Quote hidden}

Your code is fine. I'll explain the problem I had:

Let's say we have a function that returns a pointer, something like:

   int *Func1(void)
   {
       static int i;

       return &i;
   }

And let's say we invoke this function as follows:

   *Func1() = 55;

Now, instead of setting it's value to 55, let's set it to the return
value of a function called "Func2":

   *Func1() = Func2();

OK now, looking at the above statement, I ask you: Which function gets
called first, Func1 or Func2? The C Standard says that this behaviour is
"unspecified", which means that the compiler can evaluate either one of
them first, and it doesn't even have to document in its manual which one
of them gets evaluated first.

So now if we look at the original code that was something like:

   *p++ = tolower(*p);

If the right-hand side gets evaluated first, then it will behave as
though it were:

   *p = tolower(*p);
    p = p + 1;

However, if the left-hand side gets evaluated first, then it will behave
as though it were:

   p = p + 1;
   *p = tolower(*p);

The best way to avoid these problems is to shy away from reading and
writing the same variable's value in one line of code.

Note that this problem is very similar to, but distinct from, the
undefined behaviour that results from reading and writing a variable's
value without a sequence point in between. An example of a sequence
point violation would be:   j = i++  *   i++;

2008\07\23@161725 by William \Chops\ Westfield

face picon face

On Jul 23, 2008, at 10:09 AM, Martin wrote:

>>         while (   *p++ = tolower( (char unsigned)*p )   );
>>
>> The problem here is that the behaviour is "unspecified" when it  
>> comes to
>> whether "*p++" or "*p" is evaluated first. For some reason, when I  
>> upped
>> the optimisation, "*p" became the expression that was evaluated  
>> first.
>>
> Postfix increment (n++) occurs after the value is used.

That's not the problem.  The problem is whether the left side or  
right side of the assignment is evaluated first.  (actually, I think  
it would be a problem even if it was a comparison rather than an  
assignment.)

It tends to annoy me that compiler standards writers can leave  
something relatively important like this out of their specs, while  
getting all pissy about some obscure corner.

It REALLY annoys me when compiler writers use the lack of  
specification to arbitrarily change behavior from one version to the  
next.  (I didn't see that with this particular issues, but we got  
bitten pretty hard on a change in pre-processor operation ordering  
between gcc2.95 and gcc3.4...)  Grr.

BillW

2008\07\23@165159 by Tomás Ó hÉilidhe

picon face

William "Chops" Westfield wrote:
> That's not the problem.  The problem is whether the left side or  
> right side of the assignment is evaluated first.  (actually, I think  
> it would be a problem even if it was a comparison rather than an  
> assignment.)
>  


Yes you're right, you'll get this problem in places where the following
two criteria are satisfied:
   * There is no sequence point between the two things that need to be
evaluted
   * The order of evaluation is "unspecified"


> It tends to annoy me that compiler standards writers can leave  
> something relatively important like this out of their specs, while  
> getting all pissy about some obscure corner.
>  


I believe it was deliberately left out to aid in code optimisation. For
instance, if you had a line of code such as the following:

   some_variable = Func1() + Func2() * Func(3) / Func(4);

then the compiler can call the functions in whatever order it pleases.
Supposedly this gives the compiler the freedom to produce the most
efficient machine code it can. If you wanted definitive order, you'd
need to do introduce a "sequence point", maybe like as follows:

   some_variable = Func1();
   some_variable += Func2();
   some_variable *= Func3();
   some_variable /= Func4();

For those who don't know and are wondering, a sequence point is sort of
like a "fullstop". When you reach a sequence point, everything before it
must finish being evaluated before anything after it can be evaluated.
The Standard gives a finite list of when and where a sequence point
occurs; the most common one you'll be familiar with is the semi-colon at
the end of a statement.


> It REALLY annoys me when compiler writers use the lack of  
> specification to arbitrarily change behavior from one version to the  
> next.  (I didn't see that with this particular issues, but we got  
> bitten pretty hard on a change in pre-processor operation ordering  
> between gcc2.95 and gcc3.4...)  Grr.


I suppose the only thing you can say about it is that people should
learn this stuff from the very start. The book I used for learning C was
"C++ for Dummies" (I actually started out learning C++ before I delved
into C), and very early on in the book it explained about how the order
of evaluation can be arbitrarily chosen by the compiler.

Actually this makes me think of something... it would be great to have a
tool that would scan through code looking for instances in which code
will behave differently on different systems because of unspecified
behaviour. It wouldn't even need to compile the code, it would just spit
out something like:
   Warning: The statement on line 3 can have more than one effect on
different platforms

I've heard of something called Lint, only heard of it, never used it,
but I don't think it goes into this detail. I might start a thread on
comp.lang.c and see what the lads think.

'[TECH]:: Why most published research findings are '
2008\07\23@174047 by Tony Smith

flavicon
face
> > A shame they are not (or, alas, cannot) be applied in a few other
> > 'sciences' and areas of endeavour that I won't even name
> here for risk
> > of starting a conflagration.
> >
> >
> >         Russell
>
>
> Maybe we could mosey on over to the [OT] tag and discuss
> 'science areas' that are truly bogus, such as psychology and
> psychiatric medicine.
> cc


Is that you, Tom Cruise?

Tony

'[TECH] Automatic Directory Compare Software?'
2008\07\23@200320 by Josh Koffman

face picon face
I think the best way to explain what I'm asking is to describe the situation.

I have a drive that holds my main active music collection. It's about
80GB worth of music that means a fair bit to me. I keep it on an
external drive and I have copies of the data on two other drives. I
add to the main drive fairly frequently. What that currently means is
that to ensure that my backups are current I go in to the backup
drive, delete all 80GB of data, then copy it all again. It takes quite
a while and isn't really efficient.

What I'm looking for is like a drive cloning software but that will
work on only a specific directory. It has to be manually triggered as
my backup drives aren't usually connected to the live system. What I'd
love is a small (preferably free) utility that will do a diff, find
out the missing files, and sync the backup drive to the source drive.

Any suggestions? I haven't found anything that takes care of this but
perhaps I'm looking in the wrong places?

Thanks!

Josh
--
A common mistake that people make when trying to design something
completely foolproof is to underestimate the ingenuity of complete
fools.
-Douglas Adams

2008\07\23@200758 by Marcel Birthelmer

flavicon
face
rsync

On Wed, Jul 23, 2008 at 5:02 PM, Josh Koffman <joshybearspam_OUTspam@spam@gmail.com> wrote:

{Quote hidden}

> -

2008\07\23@200933 by Bob Blick

face
flavicon
face
Hi Josh,

rsync is what I use, on both Linux and Windows. If you use it on Windows
you either need Cygwin and Perl installed, or use an rsync binary(that's
what I do). Here's a link to Windows binaries:
http://optics.ph.unimelb.edu.au/help/rsync/rsync_pc1.html

Cheers,

Bob


On Wed, 23 Jul 2008 17:02:59 -0700, "Josh Koffman" <spamBeGonejoshybear@spam@spamgmail.com>
said:
{Quote hidden}

--
http://www.fastmail.fm - Choose from over 50 domains or use your own

2008\07\23@201935 by W. Jacobs

flavicon
face
Josh,
I use Sync Toy.  It has been reliable and easy to set up.
www.microsoft.com/downloads/details.aspx?FamilyId=E0FC1154-C975-4814-9649-CCE41AF06EB7&displaylang=en
bill


Josh Koffman wrote:
{Quote hidden}

2008\07\23@202923 by Herbert Graf

flavicon
face
On Wed, 2008-07-23 at 17:02 -0700, Josh Koffman wrote:
> I think the best way to explain what I'm asking is to describe the situation.
>
> I have a drive that holds my main active music collection. It's about
> 80GB worth of music that means a fair bit to me. I keep it on an
> external drive and I have copies of the data on two other drives. I
> add to the main drive fairly frequently. What that currently means is
> that to ensure that my backups are current I go in to the backup
> drive, delete all 80GB of data, then copy it all again. It takes quite
> a while and isn't really efficient.
>
> What I'm looking for is like a drive cloning software but that will
> work on only a specific directory. It has to be manually triggered as
> my backup drives aren't usually connected to the live system. What I'd
> love is a small (preferably free) utility that will do a diff, find
> out the missing files, and sync the backup drive to the source drive.
>
> Any suggestions? I haven't found anything that takes care of this but
> perhaps I'm looking in the wrong places?

A quick and dirty way:

ls /directory1 |sort > dir1_list
ls /directory2 |sort > dir2_list
diff dir1_list dir2_list | grep ">" > result

then a little "vi" and you've built a copy script. To automate pipe
result into a simple perl script that adds the appropriate copy command
and does the copy.

TTYL

2008\07\23@210847 by Josh Koffman

face picon face
On Wed, Jul 23, 2008 at 5:29 PM, Herbert Graf <RemoveMEmailinglist4EraseMEspamKILLspamfarcite.net> wrote:
> A quick and dirty way:
>
> ls /directory1 |sort > dir1_list
> ls /directory2 |sort > dir2_list
> diff dir1_list dir2_list | grep ">" > result
>
> then a little "vi" and you've built a copy script. To automate pipe
> result into a simple perl script that adds the appropriate copy command
> and does the copy.

Hm...should have mentioned that this machine is a Windows one.

That and I'm not as good at shell scripting as I used to (and I was
never really that good).

Thanks though!

Josh
--
A common mistake that people make when trying to design something
completely foolproof is to underestimate the ingenuity of complete
fools.
-Douglas Adams

2008\07\23@210958 by Josh Koffman

face picon face
On Wed, Jul 23, 2008 at 5:19 PM, W. Jacobs <spamBeGonewh2007spam_OUTspamRemoveMEcitlink.net> wrote:
> Josh,
> I use Sync Toy.  It has been reliable and easy to set up.
> www.microsoft.com/downloads/details.aspx?FamilyId=E0FC1154-C975-4814-9649-CCE41AF06EB7&displaylang=en
> bill

Aha! I totally forgot about Sync Toy. The 1.4 version wouldn't start
for me (this is a WinXP64 box) but the 2.0 version seems to have
worked. Thanks!

And for the folks who suggested rsync...I'm now looking in to it as a
backup too.

Thanks!

Josh
--
A common mistake that people make when trying to design something
completely foolproof is to underestimate the ingenuity of complete
fools.
-Douglas Adams

2008\07\23@224017 by Apptech

face
flavicon
face
XXCOPY.
XCOPY supersupersuperb-set

Old versions free. Also some features of the older ones are
better.


{Quote hidden}

       Russell


2008\07\23@234055 by Alex Harford

face picon face
On Wed, Jul 23, 2008 at 5:02 PM, Josh Koffman <.....joshybearspamRemoveMEgmail.com> wrote:
>
> What I'm looking for is like a drive cloning software but that will
> work on only a specific directory. It has to be manually triggered as
> my backup drives aren't usually connected to the live system. What I'd
> love is a small (preferably free) utility that will do a diff, find
> out the missing files, and sync the backup drive to the source drive.

I use rdiff-backup, on both Linux and Windows, it's rsync based.  Like
rsync, it can do network or local copies.

'[Tech] What to do about compiler bug and source co'
2008\07\24@031101 by William \Chops\ Westfield

face picon face

On Jul 23, 2008, at 1:51 PM, Tomás Ó hÉilidhe wrote:

>> we got bitten pretty hard on a change in pre-processor operation  
>> ordering
>> between gcc2.95 and gcc3.4...  Grr.
>
> I suppose the only thing you can say about it is that people should
> learn this stuff from the very start.

Not all the undefined issues are as obvious.  Consider:

  #define errno retrieve_errno_func()

  #define SUBSYSTEM_INCLUDE(subsystem, file) <subsystem/include/file>

  #include SUBSYSTEM_INCLUDE(posix, errno.h)

Each piece looks OK.  gcc2.95 pre-processes as intended, to:
   #include <posix/include/errno.h>
gcc3.4 preprocessed to:
   #include <posix/include/retrueve_errno_func()>
Oops.

> it would be great to have a tool that would scan through code  
> looking for instances in which code will behave differently on  
> different systems because of unspecified
> behaviour. It wouldn't even need to compile the code, it would just  
> spit
> out something like:
>     Warning: The statement on line 3 can have more than one effect  
> on different platforms

There's a whole class of tools called "static analysis" tools that do  
this sort of thing.  And for that matter, compilers themselves keep  
getting fussier as well; what WAS  accepted and compiled to correct  
code in one version may get warning messages from a later compiler.  
When we upgrade compilers, it's always a major effort to go through  
and address all the new warnings that get printed (some are actual  
errors,
some are spurious, some are due to a change in features, etc.  Policy  
is that no warning messages are allowed...)  Some things get changed,  
sometime obscure compiler switches are invoked to change behavior,  
sometimes we go and get the compiler changed to accept things the way  
we'd like them to be... ("It's all very nice that you check the  
printf arguments against the format descriptors, but we have our own  
version of printf with DIFFERENT meanings for %e and such, so you've  
got to at least have a way to turn it off!")

What you currently do (-pedantic -ansi -Wall) is a step in the right  
direction.

>
> I've heard of something called Lint ...
That's one of them.  See
  http://web.mit.edu/sunsoft_v5.1/www/c-compiler/user_guide/
lint.doc.html

There's also flexeLint, KLOCwork, Prefix, Coverity, and many others.  
Some cost big bucks.  Some are worth it (so we believe.)  Often one  
gets very frustrated with the false positives...

BillW

'[TECH] Automatic Directory Compare Software?'
2008\07\24@031636 by Artem Zezyulinskiy

flavicon
face
Hi, Josh

I use xcopy (on windows machine):
xcopy "C:\start_directory\*.*" "N:\destination_dir" /E /I /Y /D
/E - copy of dir and sub-dir
/I - create new dir if need
/Y - yes to replacements of existing files
/D - copy only modified files

you can use others options of xcopy, to see the list do : c:\xcopy /?

I hope this will aid

Artem

Josh Koffman a écrit :
{Quote hidden}

>

2008\07\24@033448 by Josh Koffman

face picon face
On Thu, Jul 24, 2008 at 12:15 AM, Artem Zezyulinskiy
<EraseMEartemzezRemoveMEspamSTOPspamsedatelec.com> wrote:
> I use xcopy (on windows machine):
> xcopy "C:\start_directory\*.*" "N:\destination_dir" /E /I /Y /D
> /E - copy of dir and sub-dir
> /I - create new dir if need
> /Y - yes to replacements of existing files
> /D - copy only modified files
>
> you can use others options of xcopy, to see the list do : c:\xcopy /?

Hi Artem,

Thanks for the advice. I wonder if the /d flag would work for new
_and_ modified files or if it's just for existing files that are
modified. Anyway it isn't a big deal as I'm using Sync Toy now.

Thanks!

Josh
--
A common mistake that people make when trying to design something
completely foolproof is to underestimate the ingenuity of complete
fools.
-Douglas Adams

2008\07\24@035912 by Apptech

face
flavicon
face
Artem -

Have a look at XXCOPY.
You'll never go back ! :-)

       http://www.xxcopy.com

Freeware and for $ versions.

I found that the latter versions were less friendly across a
network (can't recall what the issue was) and long ago I
reverted to an older version.
Far far more capable than XCOPY.

Latest copy on the above site.

Version I use at

       http://others.servebeer.com/misc/xxcopy.exe


       Russell




I use xcopy (on windows machine):
xcopy "C:\start_directory\*.*" "N:\destination_dir" /E /I /Y
/D
/E - copy of dir and sub-dir
/I - create new dir if need
/Y - yes to replacements of existing files
/D - copy only modified files

____________________________________


2008\07\24@044227 by Artem Zezyulinskiy

flavicon
face
Yes, it works for new _and_ modified files.

I created a batch file with this command and a windows planified task to
execute file on widows start up (open a session).
But i don't find anything to do this on close session.

Do you know how i can execute a file on Windows Shut-down or Session close?

Josh Koffman a écrit :
{Quote hidden}

--
Artem ZEZYULINSKIY
SEDATELEC, Chemin des Mûriers
Irigny, 69540, FRANCE
Tel : +33 [0] 472 663 326

2008\07\24@045037 by Artem Zezyulinskiy

flavicon
face
Thank, Russel

I have download free xxcopy version. It's more powerfull that simple
xcopy :)

But for this time i'm happy with xcopy.


Apptech a écrit :
{Quote hidden}

2008\07\24@051549 by Tony Smith

flavicon
face
> Josh,
> I use Sync Toy.  It has been reliable and easy to set up.
> www.microsoft.com/downloads/details.aspx?FamilyId=E0FC1
154-C975-4814-9649-CCE41AF06EB7&displaylang=en
> bill


I used to use SyncToy, (well, only a few times), I liked it until someone
here pointed out it leaves little droppings all over the place.  I hadn't
noticed, but it does; it creates little temp or id files in the directories.

Other than that it works well for the price.

Tony

2008\07\24@070706 by Josh Koffman

face picon face
On Thu, Jul 24, 2008 at 2:14 AM, Tony Smith <spamBeGoneajsmithspam@spam@beagle.com.au> wrote:
> I used to use SyncToy, (well, only a few times), I liked it until someone
> here pointed out it leaves little droppings all over the place.  I hadn't
> noticed, but it does; it creates little temp or id files in the directories.
>
> Other than that it works well for the price.

Hm...I had a poke around and you are right, there are some .dat files
that it has placed there. For the moment I'll just accept it as it
only seems to have placed the files in the root directory of what I'm
syncing. So since I'm syncing two directories (plus subs) there's only
two files. Not so bad...

Josh
--
A common mistake that people make when trying to design something
completely foolproof is to underestimate the ingenuity of complete
fools.
-Douglas Adams

'[Tech] What to do about compiler bug and source co'
2008\07\24@090430 by Tomás Ó hÉilidhe

picon face


William "Chops" Westfield wrote:
> Not all the undefined issues are as obvious.  Consider:
>
>    #define errno retrieve_errno_func()
>
>    #define SUBSYSTEM_INCLUDE(subsystem, file) <subsystem/include/file>
>
>    #include SUBSYSTEM_INCLUDE(posix, errno.h)
>
> Each piece looks OK.  gcc2.95 pre-processes as intended, to:
>     #include <posix/include/errno.h>
> gcc3.4 preprocessed to:
>     #include <posix/include/retrueve_errno_func()>
> Oops.


I wonder if the Standard says anything about which one of them if
correct. My guess is that gcc3.4 is correct (even though it didn't
behave as intended!). I'll look into it and get back to you.

'[TECH]:: Why most published research findings are '
2008\07\24@093411 by Matthew Rhys-Roberts

flavicon
face
For further interest, an in relation to the more recent PIClist thread
regarding mobile phones and cancer, please see also
http://www.powerwatch.org.uk/science/bias.asp

Matt

Apptech wrote:
> The claim that 'most published research findings are false',
> while demonstrably true, is so utterly contrary to intuition
> and to what we think we know about research methods,
> statistical analysis and more as to be rejected out of hand
> by many.
>  
[snip]

'[TECH] The DelFly Micro Air Vehicle'
2008\07\24@110410 by Alex Harford

face picon face
www.tudelft.nl/live/pagina.jsp?id=1468ded9-96cb-47dd-aed3-da0a70a34813&lang=en

Haven't been able to find any details about the electronics on board. :(

Size: 10 cm, from wingtip to wingtip
Weight: 3.07 gram;
Battery: 1 gram
Camera and transmitter: 0.4 gram;
Engine: 0.45 gram;
Receiver: 0.2 gram;
Actuators: 0.5 gram;
Rest: about 0.52 grams.
Battery: 30 mah lithium polymer, for three minutes fight.
Flap frequency wings: 30 Hz
Materials: Mylar foil (wings), carbon and balsawood.
Range: 50m

'[TECH]:: Why most published research findings are '
2008\07\24@195159 by Cedric Chang

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I read this paper and the authors make some pretty amazing leaps of  
logic.  This does not mean they are wrong and I believe they are  
probably right ; still it makes me realize what a cat's bag of  
confusion most information packets are these days.  Probably for the  
past 10,000 years as well.
cc

{Quote hidden}

'[TECH] Automatic Directory Compare Software?'
2008\07\25@003005 by Vitaliy

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Apptech wrote:
> Have a look at XXCOPY.
> You'll never go back ! :-)
>
>        http://www.xxcopy.com

I actually bought a license for my machine at work (after Russell suggested
it a while back). Great program.

Vitaliy

'[TECH]:: TECH membership'
2008\07\25@075303 by Matthew Rhys-Roberts

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#1 applies to me  :)

I didn't know it was possible to un/subscribe other tags. Or I'd
forgotten there was an email list preferences form somewhere.

Matt
Wrexham, UK


Apptech wrote:
> I'd be interested in knowing how many people
>
> 1.    Are receiving TECH tag material automatically.
> 2.    Have explicitly subscribed to TECH
> 3.    Have been automatically subscribed but intent to
> unsubscribe.
>  

2008\07\25@131835 by Sean Breheny

face picon face
Same here.

On Mon, Jul 14, 2008 at 9:54 AM, Picbits Sales <RemoveMEsalesspam_OUTspampicbits.co.uk> wrote:
> I'm getting it automagically without having to change anything in my Piclist
> settings.
>
> I think I've got mine to receive all posts
>
> Dom
> {Original Message removed}

2008\07\25@143209 by Stephen D. Barnes

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>
>>> I'd be interested in knowing how many people
>>>
>>> 1.    Are receiving TECH tag material automatically.
>>> 2.    Have explicitly subscribed to TECH
>>> 3.    Have been automatically subscribed but intent to
>>> unsubscribe.
>>>      
#2 for me.

--
Regards,
Stephen D. Barnes

'[TECH] Better-designed CFL's?'
2008\07\26@054350 by Forrest Christian

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The lighting in my house is almost 100% CFL's.  However, I've got a
couple of locations that seem to resist the use of a CFL.   I was
wondering if anyone had any input into how to find a CFL useful for
those spots.

The first spot is a light fixture which is attached to a ceiling fan.  
For whatever reason, this spot seems to eat CFL's.   That is, the CFL's
don't seem to last even as long as a Incandescent in this location.  
Other than the fan, the only unique thing about this location is that it
is attached to a X10 fluorescent-rated appliance-style wall switch,
which I've used similar ones of before and never had a problem, so I can
only assume there is something either about the vibration or about the
fan motor sharing a neutral with the CFL.  I've tried a couple of
different types in here with the same effect.  I've seen "fan CFL's" -
but these seem to be only a CFL in a prettier enclosure (globe covering
the CFL tube), and quite a bit more expensive.   Plus, they only seem to
be available locally in low wattage - I need a 75 or 100W equivalent at
this location.

The other location is in an area which gets cold in the winter.  
Evidentally CFL's don't like sub-zero temps.  The current one won't even
start in sub-zero temps - and will actually shut itself off if it gets
too cold.   I've had others in there, but none that I would call even
close to a cold-weather success.    It also seems that operating
temperatures aren't listed on these things.  

Both of these are in locations where it is a pain to change the bulb, so
I really want to run a CFL - for longevity as much as energy savings.  
But I haven't found anything that actually seems to work yet.

I would have thought that some higher-quality CFL's would have sprung up
for situations like these but the manufacturers all seem to be focusing
on trying to get and keep the costs around $1/bulb.

Ideas?

-forrest


2008\07\26@112306 by Herbert Graf

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On Sat, 2008-07-26 at 03:42 -0600, Forrest Christian wrote:
> The lighting in my house is almost 100% CFL's.  However, I've got a
> couple of locations that seem to resist the use of a CFL.   I was
> wondering if anyone had any input into how to find a CFL useful for
> those spots.
>
> The first spot is a light fixture which is attached to a ceiling fan.  
> For whatever reason, this spot seems to eat CFL's.   That is, the CFL's

My guess is it's the enclosed "upside down" they don't like. CFLs can
run hot, they are not designed to run upside down and enclosing them is
even worse.

> The other location is in an area which gets cold in the winter.  
> Evidentally CFL's don't like sub-zero temps.  The current one won't even
> start in sub-zero temps - and will actually shut itself off if it gets
> too cold.   I've had others in there, but none that I would call even
> close to a cold-weather success.    It also seems that operating
> temperatures aren't listed on these things.  

This one doesn't make sense. I have multiple bulbs outdoors, and in the
winter they work fine. When it's really cold (< -20C) they may take a
minute or two to reach full brightness, but aside from that they always
work.

As a solution to your problems, first thing I'd do is buy a Phillips
Marathon CFL. While they are a little more expensive, they are the best
performing ones I've used. Generally, they start up REALLY quickly
(usually indistinguishable from an incandescent), reach full brightness
very quickly, and so far I haven't had one fail.

OTOH cheaper brands have many issues. They either start up slowly,
and/or take a long time to get to full brightness, even when warm. I
have had a few of those fail, in each case they were replaced with a
Phillips bulb and since then no failures.

TTYL

2008\07\26@153450 by Forrest W Christian

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Herbert Graf wrote:
> My guess is it's the enclosed "upside down" they don't like. CFLs can
> run hot, they are not designed to run upside down and enclosing them is
> even worse.

Not designed for "upside down"?  Really?   I would say that over 75% of
the CFL's  have in place, and know of in place, are Upside down - that
is the base is on the ceiling and the bulb is hanging down - opposite of
what you'd have in say a table lamp (the type of with a lampshade).
That is an interesting tidbit.

This particular bulb isn't enclosed right now either (when the second
one failed, I left the globe off to help try to diagnose the problem
easier).

> This one doesn't make sense. I have multiple bulbs outdoors, and in the
> winter they work fine. When it's really cold (< -20C) they may take a
> minute or two to reach full brightness, but aside from that they always
> work.

Maybe I should have clarified sub-zero.   For me, sub-zero means
sub-zero F...  That is, below -20*C.    During December and Jan, the
average low is around -10*C, with many days lower than that.   The
average high during those same months is not above freezing.  So these
bulbs get *cold*.

Down to a certain temperature they typically start slower, but never
reach their full light potential.   Colder than that they often don't
start.   The one that's in there right now could be a -20*C detector if
coupled with a suitable light sensor.

{Quote hidden}

That's the information I was looking for.   I've bought "expensive"
bulbs in the past, but as you probably know "expensive" does not
necessarily equal quaility... sometimes it means a business decision to
sell more at a larger margin.

-forrest

2008\07\26@155151 by Vitaliy

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Forrest W Christian wrote:
>> My guess is it's the enclosed "upside down" they don't like. CFLs can
>> run hot, they are not designed to run upside down and enclosing them is
>> even worse.
>
> Not designed for "upside down"?  Really?

I had the same reaction, and I think Herbert is thinking of the problems
caused by operating the CFLs horizontally, not when they're used in the
usual ("upside down") manner.

My CFLs didn't last long in the ceiling fan fixture, but I'm fairly certain
that was because it has a dimmer switch.

{Quote hidden}

IIRC, it was Herbert who suggested using Philips bulbs in a similar thread a
while back, and I must say the difference is indeed very drastic (just as he
describes). Paradoxically, Philips bulbs weren't that much more expensive
(certainly not x2) than the other CFLs available at the store.

Vitaliy

PS You probably meant to say "..a business decision to sell LESS at a larger
margin" in your last sentence. Higher price = lower demand.

2008\07\27@003210 by Bob Blick

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Vitaliy wrote:

> IIRC, it was Herbert who suggested using Philips bulbs in a similar
> thread a while back, and I must say the difference is indeed very
> drastic (just as he describes). Paradoxically, Philips bulbs weren't
> that much more expensive (certainly not x2) than the other CFLs
> available at the store.

Philips does seem to have pretty good QC compared to off-brands.

In California CFL's are subsidised by the electric company. I have never
paid more than about a dollar for a CFL. Last time I bought some
(Philips brand at Costco) they were about $.75 for the "60 watt
equivalents" and $1.05 for the "100 watt equivalents".

Consequently I use them almost everywhere. The name brands have nicer
light and fewer early failures than the generics. But basically they
last a long time on average. Failure modes are pretty varied. Some have
almost melted down.

Slow starting at low temperatures and short lifespan at high
temperatures. So I don't use them in outdoor fixtures or in the attic.

I prefer them to white LEDs in terms of light quality. I have trouble
seeing with the light from white LEDs.

Cheerful regards,

Bob

2008\07\27@005416 by Forrest Christian

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Vitaliy wrote:
> PS You probably meant to say "..a business decision to sell LESS at a
> larger margin" in your last sentence. Higher price = lower demand.
Yes, that is what I meant to say :)

-forrest

2008\07\27@030945 by Vitaliy

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Bob Blick wrote:
> In California CFL's are subsidised by the electric company. I have never
> paid more than about a dollar for a CFL. Last time I bought some
> (Philips brand at Costco) they were about $.75 for the "60 watt
> equivalents" and $1.05 for the "100 watt equivalents".

Bob, since issue has come up in another thread, I would like to point out
that "subsidized" in this case simply means that government took your money,
gave it to the electric company (a government-protected monopoly), and let
it decide what kind of CFLs you should use. TANSTAAFL.

> Consequently I use them almost everywhere. The name brands have nicer
> light and fewer early failures than the generics. But basically they
> last a long time on average. Failure modes are pretty varied. Some have
> almost melted down.

I found that the difference is huge. Philips bulbs are instant-on, produce
better color spectrum, and last several times longer than generics. They
cost only about $1 more than unsubsidized generics.

Vitaliy

'[TECH]:: TECH membership'
2008\07\27@031829 by Ray Warren

picon face
On Tue, Jul 15, 2008 at 01:02:26AM +1200, Apptech wrote:

> I'd be interested in knowing how many people
>
> 1.    Are receiving TECH tag material automatically.
> 2.    Have explicitly subscribed to TECH
> 3.    Have been automatically subscribed but intent to
> unsubscribe.
>
> Reply to onlist preferably or to me if you don't want to
> de-lurk visibly.
>
> Not the sort of thing we'd probably usually do much of in
> TECH but useful for people to see who is present here.
>
>
>
>         Russell
I am receiving the TECH material automatically.I do not have any filters
set on the piclist site,
Ray Warren

'[TECH] Set pixel for Linux'
2008\07\27@090737 by Peter Onion

flavicon
face

On Mon, 2008-07-21 at 20:53 -0400, M. Adam Davis wrote:
> Direct x-windows (ie, no need to fiddle with finicky toolkits, etc):
>
> http://marvel.incheon.ac.kr/infomation/xwindow/Xwindows%20Programming.htm

IMNSHO xlib is far more "finicky" than using gtk or gdk.

If you have gtk installed, try running gtk-demo.  There is example code
in there for the drawing area widget.

PeterO



'[TECH] Better-designed CFL's?'
2008\07\27@110948 by Bob Blick

face
flavicon
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Vitaliy wrote:

> Bob, since issue has come up in another thread, I would like to point out
> that "subsidized" in this case simply means that government took your money,
> gave it to the electric company (a government-protected monopoly), and let
> it decide what kind of CFLs you should use. TANSTAAFL.

I notice you have an interest in this "government is bad" idea. I have
seen lots of American historical motion pictures called "Westerns" and
it looks like the United States before "big government" wasn't such a
nice place even for gunslingers with lots of talent. Life seemed pretty
risky. And they didn't have modern forms of lighting like CFLs either.

There are plenty of places where government doesn't "take your money":
US Virgin Islands, Monaco, Dubai etc but I notice you don't choose to
live there. Why not, could it be there are other factors that are more
important? I don't mind "big government" "taking my money". I am doing
just fine thank you. Big government in California is responsible for the
clean air we now have. I remember Los Angeles air forty years ago. Every
time I am stuck in traffic in another state the smell of exhaust
surprises me until I remember they don't have such "big government"
regulations preventing them from having gross polluters on the road.

So perhaps I think giving incentives for people to use less energy has
multiple benefits, some may not be obvious.

But in my original email I really only mentioned the price subsidy
because I was thinking about my reasons for trying CFLs in every
possible application. At those prices it's hard not to.

Cheerful regards,

Bob

2008\07\27@123545 by Harold Hallikainen

face
flavicon
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While I support efficient energy use, I've found that CFLs either don't
fit in our fixtures or don't produce enough light. We have several rooms
with built-in fluorescent tubes, and I try to keep lights off when
possible, but there are still a few incandescents.

I read a while back about an efficient incandescent lamp that was based on
nanotechnology. As I recall, there was something that only allowed visible
light to escape the lamp. IR was not allowed to escape, thus preventing
that energy loss from cooling the filament (less power needed to maintain
the filament temperature). I've heard of proposals to outlaw incandescent
lamps, but think it might be better to put minimum efficiency standards on
lamps to allow whatever technology most cost effectively meets the
requirements.

Harold

--
FCC Rules Updated Daily at http://www.hallikainen.com - Advertising
opportunities available!

2008\07\27@144046 by Cedric Chang

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{Quote hidden}

The government may not take your money in those places, yet it is  
still bad.  Dubai imposes severe restrictions on your life style.  I  
don't know much about Virgin Islands or Monaco.  Do they allow you to  
ingest drugs of your choice ?  Maybe I will move there.
cc


{Quote hidden}

> --

2008\07\27@144712 by Carl Denk

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For the fluorescent tubes, the T-8 configuration with electronic
ballasts save considerable power. A few months back I posted the
comparison, and for lights on 12 hours a day, 48" long tubes, based on
my actual amps of current drawn measurement, the pay back was like 18
months. It cost me $35 /2 tube fixture to convert which was 2 green
tubes, 4 sockets (not required, the tubes use same socket, but these
were old and cracking), and an electronic ballast.

Harold Hallikainen wrote:
{Quote hidden}

2008\07\27@145630 by Chris Smolinski

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What's a good *bright* fluorescent (or CFL if it exists) solution for
lighting an office room? Say around 12 by 15 ft. I have one overhead
fluorescent lamp now, I forget the type, it uses the U shaped bulbs.
40 watts or so? It isn't terribly bright. So I end up using a 300W
halogen torchiere lamp also.  I'm doing detail work (soldering etc)
so I need good light.

--

---
Chris Smolinski
Black Cat Systems
http://www.blackcatsystems.com

2008\07\27@184519 by Apptech

face
flavicon
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>> While I support efficient energy use, I've found that
>> CFLs either don't
>> fit in our fixtures or don't produce enough light.

I've found that the 100 Watt *input* CFLs produce a very
nice amount of light :-).

One tends to need to remove lampshades for them to fit :-).

For those who have not seen these "monsters".

   http://others.servebeer.com/misc/cfl1.jpg
   http://others.servebeer.com/misc/cfl2.jpg

And with these you can save a lot more energy at a time per
bulb.


       Russell



2008\07\27@193844 by Carl Denk

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I think the T-8 comes U-shaped, if so, that should be an easy change,
just change the ballast and lamp. On the other hand, if the fixture is
not say part of the ceiling or some other architectural detail, likely
new fixtures with 2 or 4 48" straight tubes will be better long term.
Probably for a room that size, (2) 2 tube fixtures will suffice, but if
shadows in the corners are an issue, might just want 1 row of 2 fixtures
centered on the short side, parallel to the short side and
4' or so from the short sides. Then use task lighting where you need
bright light.

Chris Smolinski wrote:
> What's a good *bright* fluorescent (or CFL if it exists) solution for
> lighting an office room? Say around 12 by 15 ft. I have one overhead
> fluorescent lamp now, I forget the type, it uses the U shaped bulbs.
> 40 watts or so? It isn't terribly bright. So I end up using a 300W
> halogen torchiere lamp also.  I'm doing detail work (soldering etc)
> so I need good light.
>
>  

2008\07\28@003415 by Forrest Christian

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Chris Smolinski wrote:
> What's a good *bright* fluorescent (or CFL if it exists) solution for
> lighting an office room? Say around 12 by 15 ft. I have one overhead
> fluorescent lamp now, I forget the type, it uses the U shaped bulbs.
> 40 watts or so? It isn't terribly bright. So I end up using a 300W
> halogen torchiere lamp also.  I'm doing detail work (soldering etc)
> so I need good light.
>  
We use a shop light with either 40W or 25W tubes about 3ft above the
work bench.  (Usually the 40W's since the light seems to be better clarity).

It very specifically gets plugged into the same power strip as all of
the things which must be turned off at night for safety - and has no
separate switch of it's own.   So, if the bench is on, it's on.  Works
great.

-forrest

'[TECH]:: Wonderful web resource'
2008\07\28@004239 by Apptech

face
flavicon
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I'll pass this on as it came to me :-).
Seems enough technology in there ...

_____________

Russell,

I have probably "raved on" about this before but here is a
simply stunning
repository of out-of-copyright and non-copyright material
covering a wide
range of subjects all freely available for download:

http://www.archive.org/index.php

>From the amazing (and ultimately very silly) Pipe Dream
music video from
1991 here:

http://www.archive.org/details/PipeDrea2001

to a book of illustrations of dancing dating from 3300 BC, a
facsimile of
the orignal book which became Alice in Wonderland (from
Project Gutenberg),
to a book published in 1904 on the subject of building your
own steam
turbine  - and much else besides.

Need an animated GIF of a wind turbine  - there's one here:

http://www.archive.org/details/Offshore_Wind_Turbine__Small_1

Interested in a set of videos showing the construction of a
large wind
turbine  - they have movies for a wind farm built at Hull in
Massachusetts.

Be warned   - You could lose a lot of time (and use up a lot
of your
Internet traffic allowance) on this website.



Regards,

Ken Mardle

'[TECH] Better-designed CFL's?'
2008\07\28@043301 by Vitaliy

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Bob Blick wrote:
> I notice you have an interest in this "government is bad" idea.

I prefer to express my position as "government is a necessary evil" ( (C)
Thomas Paine).

> I have
> seen lots of American historical motion pictures called "Westerns" and
> it looks like the United States before "big government" wasn't such a
> nice place even for gunslingers with lots of talent.

You will forgive me if I say I don't consider Westerns to be a reliable
source of information about that era of US history. :-)

> Life seemed pretty
> risky.

Residents of certain cities (Killadelphia?) would argue that life seems
pretty risky now. At least back then, AKs weren't as common.

> And they didn't have modern forms of lighting like CFLs either.

Are you suggesting that we should credit big government with the invention
of the CFL? :)

> There are plenty of places where government doesn't "take your money":
> US Virgin Islands, Monaco, Dubai etc but I notice you don't choose to
> live there. Why not, could it be there are other factors that are more
> important?

Yes. As Cedric noted, some of the places limit one's freedom in other ways.
Also, being able to visit family at least once a year (geographic proximity)
is important.

However, one of the reasons I choose not to live in California or
Washington, for example, is because they have big governments. Arizona is
more business-friendly.

> I don't mind "big government" "taking my money". I am doing
> just fine thank you.

May I ask what you do/did for a living? And why you think it's OK for the
government to take your money?

> Big government in California is responsible for the
> clean air we now have.

Is it the same government responsible for the rolling blackouts? :)

But seriously, this is a bad example to support your argument. The cost of
cleaning up the air was borne almost exclusively by the manufacturers and
the consumers (car buyers).

> I remember Los Angeles air forty years ago. Every
> time I am stuck in traffic in another state the smell of exhaust
> surprises me until I remember they don't have such "big government"
> regulations preventing them from having gross polluters on the road.

All states obey the same regulations dictated by the EPA (they're based on
CARB regulations). Enough time had passed since the regulations went into
effect nationwide (1996) so that vehicles in California pollute about as
much as vehicles in other states. FWIW, the air in Phoenix is cleaner, and
there's definitely less smog than in LA.

Mind you, I'm all for clean air. I believe that in a limited number of
situations it is OK for the government to compensate for an externality,
especially in cases where the harm to society outweighs the benefits (or the
benefit to society far outweighs the cost).

http://en.wikipedia.org/wiki/Market_failure

> So perhaps I think giving incentives for people to use less energy has
> multiple benefits, some may not be obvious.

If the goal is to save energy, the incentive should reward people for saving
energy, not buying inferior quality CFLs.

There are much better ways to create the incentive, for example:

1. Let the market price of electricity reflect its actual cost. The best way
to accomplish this is to deregulate the energy sector.

2. Give people vouchers, that can be used to buy any CFLs of consumer's
choice.

3. Provide tax breaks.

In general, it's a bad idea to encourage people to use a particular
technology (CFLs, catalytic converters, etc), it's better to align the
incentive as closely as possible with the stated goal.

Vitaliy

'[TECH]:: Space Elevators'
2008\07\28@075452 by Apptech

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> What happened to the ladder to heaven we were going to
> build?

Tower of Babel, did you say? :-)

Presumably you mean the "beanstalk" / space elevator / ...
It is almost practical now for limiting values of practical.
ie the "taper" rate depends on the strength of the material
used. The best material available now COULD (probably) be
used to build one, but the taper rate is ugly. If the
material scientist boyos keep chugging along at current
rates it will keep on getting more practical and start to
approach downright compelling in a few decades. (When they
start *seriously* talking about building a single span
suspension bridge across the Straits of Gibralta it's bean
stalk time. Materials requirements are roughly equal.
This version cheats - only 5000 metre spans (!)
   http://www.opacengineers.com/index.php?menu=projectsheet,Gibraltar

Beanstalks have other issues apart from pure implementation
practicality. You have to build them from the top down or
top down with fly in or similar. Having a lot better/cheaper
access to space (chicken and egg) and will power to do it
and need to do it would help muchly. If you can source some
materials from 'out there' it saves hauling it from 'down
here' which can help. The idea of making this sort of thing
from material gained from 'out there' is liable to rather
add to the delays.

If you break one of these, depending where you break it. it
will want to wrap itself all the way round the world a
number of times. That could be an extremely bad thing to be
anywhere near, quite apart from what the shareholders and
insurers are liable to say. If you do build one then placing
a nuke or other suitable device on board becomes the #1
dream of every 911_upstager_wannabee going. Trying to fly
anthing, however innocuous, anywhere near it would guarantee
flight 007 / USS Vinciennes type results instantly. Deciding
who is "allowed" to build something that so dominates so
many aspects of earth and who allows them to will be
interesting questions. If there are N of these (N >1) then
you really really really don't want even 1 of them to fall
down! Mayhaps (and I just made this up) by making them
resonant and slightly off equator you MAY be able to make
them mutually non interfering in the case of a disaster.
(Resonant beanstalks have been proposed for eg Mars to allow
them to dodge the moons which are below the beanstalks
necessary minimum height.)(Or is that only one of the
moons - too lazy / forget - look it up yourself). A static
beanstalk must have its feet on the equator but perhaps a
dynamically oscillating oen can be offset slightly. Perhaps.

Kim Stanley Robinson is his stunningly marvellous
Red/Green/Blue Mars fiction trilogy did a fair job of
discussing the making and breaking of beanstalks.

Many refs below.


       Russell

Here's one on 'some world somewhere'.
Nice picture.

       http://www.blog.speculist.com/archives/06_SpaceElevator.jpeg

A fw people [tm] are interested:

       http://www.spaceelevator.com/

       http://www.spaceelevatorblog.com/

       http://www.liftport.com/

       http://en.wikipedia.org/wiki/Space_elevator

       http://www.space.com/businesstechnology/technology/space_elevator_020327-1.html

NASA ! :-)

       http://science.nasa.gov/headlines/y2000/ast07sep_1.htm

       http://www.spaceward.org/elevator2010


2008\07\28@083508 by Mike Hord

picon face
en.wikipedia.org/wiki/Launch_loop
http://en.wikipedia.org/wiki/Space_fountain

What about these guys?  I know you've mentioned them before.

I prefer these to the space elevator, largely because I've READ KSR's
description of what happens when one fails...

Mike H.

On Mon, Jul 28, 2008 at 6:52 AM, Apptech <apptechspamspamparadise.net.nz> wrote:
{Quote hidden}

> -

2008\07\28@093322 by Apptech

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en.wikipedia.org/wiki/Launch_loop
http://en.wikipedia.org/wiki/Space_fountain

> What about these guys?  I know you've mentioned them
> before.

Take the fountain to its logical extreme and you have a
LASER launcher :-)
The pellets become photons and the tower structure is no
longer needed.

The loop sounds good but it tends to rely on extremely high
tech and uncertainty.

Of the 3 I'd feel happiest about investing in a launch LASER
system once they had the "engineering problems" [tm] sorted
out.


           Russell


'[TECH] Personal air transport'
2008\07\29@085208 by Jinx

face picon face
(Almost [EE] but not quite)

Developed in New Zealand by Glenn Martin, public unveiling at
2008 Oshkosh Air Show

http://www.airventure.org/2008/news/080710_jetpack.html

More details are emerging about "The World's First Practical Jetpack"
that will make its public debut at EAA AirVenture on Tuesday, July 29

http://www.youtube.com/watch?v=eAsommyN2gQ

http://www.nytimes.com/2008/07/29/science/29jetpack.html?hp

As people point out here, it's not a jetpack. Ducted fa, as in VTOL

http://www.boingboing.net/2008/07/25/sneak-preview-of-the.html

http://en.wikipedia.org/wiki/Jet_pack

As seen on NZ TV tonight (a longer one on Sunday), the machine
did actually lift the pilot and he flew across the lawn, steadied by two
helpers

Very similar to the ducted fan built by Mythbusters some time ago

http://en.wikipedia.org/wiki/MythBusters_episodes:_Season_3

'[TECH] Canon HF100 camcorder (was: [EE] SDHC Cards'
2008\07\29@121903 by Carlos Marcano

picon face
So, Adam, how has this nice looking camera been doing?

-Carlos

On 17/07/2008, M. Adam Davis <spam_OUTstienmanspam_OUTspamspam_OUTgmail.com> wrote:
{Quote hidden}

> -

'[TECH] Now that is how I want to get to work ...'
2008\07\30@100916 by Apptech

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>> www.nzherald.co.nz/section/story.cfm?c_id=5&objectid=10524334
>> Just needs to fly a bit higher ...
>
> Alan, you might not have noticed I posted a lot about that
> under [TECH]
> Seeing as you've already opened it with [EE]

I've been biting my tongue, as it were, on this for some
days, but ...

I do hate to participate in tall poppy lopping with a fellow
NZer in the news, but, it's not obvious how this is new,
innovative or especially liable to do any better than the
numerous other attempts that it follows - some decades old.

There was a recent (few years) effort that looked very very
similar in concept but with larger rotors and a better
appearance. AFAIR one of the people on this list or perhaps
ARocket were on the development team and, they recounted,
were largely not listened to as the project self destructed.

Here we are - Solotrek.
LOOKS fantastic. WAS Fantastic - too much so.

Springtail and XFV

       http://www.roadabletimes.com/roadables-vtol_trekaero.html

XFV

       http://en.wikipedia.org/wiki/SoloTrek_XFV
       http://www.time.com/time/2001/inventions/go/infly.html

ALLEGEDLY still alive ... ? as at 2007
Walker?

       http://www.trekaero.com/

   More pictures    http://www.trekaero.com/Trek_Photos.htm





The current Martin 'Jetpack' is short on stability at
present. Even a 6 foot high to and fro unassisted demo would
have been far far far more impressive. John Carmack's 'lunar
lander' beats it to a pulp at present.

_____________

Here are only a few of the past efforts.
Some extremely successful in their niche.

       http://www.damninteresting.com/?p=722

The soldier in/on the HZ-1 deserves several medals for
bravery.

The Hiller VZ-1 Pawnee looks somewhat safer to fall off, if
not to fly.
The Piasecki VZ-8 Air Geep looks awesome and was a
successful demonstrator.

The Williams Wasp ***WAS*** a manned JET powered flying
platform with impressive performance.

There were numerous other attempts of variable successs.
___________________

Hoppi-Copter
1946
1 man strap on helicopter

       www.aviastar.org/helicopters_eng/pentecost_103.php
The man who made its engine - and much else.
Search page for Hoppi - or read it all !!!

       http://www.ctie.monash.edu.au/hargrave/righter6_part1.html


   http://www.shanaberger.com/hoppicoper.htm

Many photos

       http://images.google.co.nz/images?hl=en&q=hoppicopter&gbv=2


________________

Hiller Rotorcycle
Specs but no photo here

       http://www.hiller.org/rotorcycle.shtml


_________________________

NASA 1970
Simulator therefore

       http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19710003261_1971003261.pdf

       http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=AD0259079


Sleep time ...

           Russell

2008\07\30@114339 by Matthew Rhys-Roberts

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On an experimental aircraft related note, does anyone recall a HUGE
single-bladed monocopter made by (AFAIK) the US military? I saw this in
a rotorcraft book in my youth, and once for a few seconds on TV. The
rotor went around at about 1cps. I think there was a great big
counterweight opposing the one blade/wing in order to keep it as stable
as they could. The aircraft didn't do much, apart from provide lots of
design and test information. I would love to dig up some more info on this.

Thanks
Matt

'[TECH] Single blade helicopter (was: Now that is h'
2008\07\30@115843 by M. Adam Davis

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On 7/30/08, Matthew Rhys-Roberts <RemoveMEmattKILLspamspam@spam@nu-ins.com> wrote:
> On an experimental aircraft related note, does anyone recall a HUGE
> single-bladed monocopter made by (AFAIK) the US military? I saw this in
> a rotorcraft book in my youth, and once for a few seconds on TV. The
> rotor went around at about 1cps. I think there was a great big
> counterweight opposing the one blade/wing in order to keep it as stable
> as they could.

Perhaps the results of this search will help you find it:
http://www.google.com/search?q=helicopter+with+single+blade+rotor

Here is a discussion of the idea in general:
http://www.rotaryforum.com/forum/archive/index.php/t-7391.html

Here are two examples:
www.aviastar.org/helicopters_eng/bo-102.php
http://www.aviastar.org/helicopters_eng/bo-103.php

I'm curious about the failure mode - when the engine stops turning the
blade I assume it autorotates like any other helicopter, but does it
do so unevenly?  Is it possible that it might stall rather than turn?

-Adam

--
EARTH DAY 2008
Tuesday April 22
Save Money * Save Oil * Save Lives * Save the Planet
http://www.driveslowly.org

'[TECH] Now that is how I want to get to work ...'
2008\07\30@183950 by Mark Huffstutter

picon face
Matt,
     I think You are recalling the Hughes XH-17 experimental
Very Heavy Lift helicopter. I have some video of it somewhere....

<http://en.wikipedia.org/wiki/Hughes_XH-17>

<http://www.aviastar.org/helicopters_eng/mcdonnel_crane.php>

Regards,
Mark






On Wed, 30 Jul 2008 16:39:36 +0100, Matthew Rhys-Roberts wrote
{Quote hidden}

> --

'[TECH]:: NASA confirms liquid lake on surface of T'
2008\07\30@234901 by Apptech

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Since the availability fo data from the Cassini probe
several years ago people have thought that numerous dark
surface features on Titan's surface were liquid lakes. NASA
has decided that based on data acquired early this year, now
is the time to announce that they conclude the assumptions
are correct. (Ethane has been detected by spectroscopy.)

As one such lake is about as large as Lake Ontario (so now
named "Ontario Lacus ") and is believed to be filled with
liquid Ethane and Methane it may, one day, prove 'quite
useful'. (Atmosphere is ~ 95% Nitrogen with a Methane liquid
cycle and Ethane is formed from sunlight decomposition of
Methane

AFAIK the latest July 31st report in nature is based on a
flyby analysis in about January this year.

       http://www.nasa.gov/home/hqnews/2008/jul/HQ_08_193_Titan_lake.html

Surface temperature is 'a bit cold' at round -100 degrees
Celsius



           Russell McMahon


___________________________________


NASA Confirms Liquid Lake On Saturn Moon


PASADENA, Calif. -- NASA scientists have concluded that at
least one of the large lakes observed on Saturn's moon Titan
contains liquid hydrocarbons, and have positively identified
the presence of ethane. This makes Titan the only body in
our solar system beyond Earth known to have liquid on its
surface.

Scientists made the discovery using data from an instrument
aboard the Cassini spacecraft. The instrument identified
chemically different materials based on the way they absorb
and reflect infrared light. Before Cassini, scientists
thought Titan would have global oceans of methane, ethane
and other light hydrocarbons. More than 40 close flybys of
Titan by Cassini show no such global oceans exist, but
hundreds of dark lake-like features are present. Until now,
it was not known whether these features were liquid or
simply dark, solid material.

"This is the first observation that really pins down that
Titan has a surface lake filled with liquid," said Bob Brown
of the University of Arizona, Tucson. Brown is the team
leader of Cassini's visual and mapping instrument. The
results will be published in the July 31 issue of the
journal Nature.

Ethane and several other simple hydrocarbons have been
identified in Titan's atmosphere, which consists of 95
percent nitrogen, with methane making up the other 5
percent. Ethane and other hydrocarbons are products from
atmospheric chemistry caused by the breakdown of methane by
sunlight.

Some of the hydrocarbons react further and form fine aerosol
particles. All of these things in Titan's atmosphere make
detecting and identifying materials on the surface
difficult, because these particles form a ubiquitous
hydrocarbon haze that hinders the view. Liquid ethane was
identified using a technique that removed the interference
from the atmospheric hydrocarbons.

The visual and mapping instrument observed a lake, Ontario
Lacus, in Titan's south polar region during a close Cassini
flyby in December 2007. The lake is roughly 7,800 square
miles in area, slightly larger than North America's Lake
Ontario.

"Detection of liquid ethane confirms a long-held idea that
lakes and seas filled with methane and ethane exist on
Titan," said Larry Soderblom, a Cassini interdisciplinary
scientist with the U.S. Geological Survey in Flagstaff,
Ariz. "The fact we could detect the ethane spectral
signatures of the lake even when it was so dimly
illuminated, and at a slanted viewing path through Titan's
atmosphere, raises expectations for exciting future lake
discoveries by our instrument."

The ethane is in a liquid solution with methane, other
hydrocarbons and nitrogen. At Titan's surface temperatures,
approximately 300 degrees Fahrenheit below zero, these
substances can exist as both liquid and gas. Titan shows
overwhelming evidence of evaporation, rain, and fluid-carved
channels draining into what, in this case, is a liquid
hydrocarbon lake.

Earth has a hydrological cycle based on water and Titan has
a cycle based on methane. Scientists ruled out the presence
of water ice, ammonia, ammonia hydrate and carbon dioxide in
Ontario Lacus. The observations also suggest the lake is
evaporating. It is ringed by a dark beach, where the black
lake merges with the bright shoreline. Cassini also observed
a shelf and beach being exposed as the lake evaporates.

"During the next few years, the vast array of lakes and seas
on Titan's north pole mapped with Cassini's radar instrument
will emerge from polar darkness into sunlight, giving the
infrared instrument rich opportunities to watch for seasonal
changes of Titan's lakes," Soderblom said.

Launched in Oct. 1997, Cassini's 12 instruments have
returned a daily stream of data from Saturn's system. The
mission is a cooperative project of NASA, the European Space
Agency and the Italian Space Agency.

For information on Cassini, visit:

2008\07\31@014059 by Sean Breheny

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Hi Russell,

Out of curiosity, I worked out how long the world's present energy
consumption could be supplied by such a lake:

Volume of Lake Ontario=393 cubic miles=1.6e12 cubic meters
Assume for simplicity's sake it is pure liquid methane. Then the
density would be about 422kg/m^3
You can get as much as 50MJ per kg from methane combustion, although I
used half of this considering the need to warm it up and the max
efficiency of a thermal engine: 25MJ/kg

The world present energy use per year is about 5e20 J (as of 2005).

(1.6e12*422*25e6)/5e20=33.76 years

At this rate, the lake would last 34 years. Not all that long!

Then again, this side-steps all the trouble which you would have to
take in order to transport it back to Earth (unless you were thinking
of some ways to use it out in space, such as fuel for a spacecraft or
a settlement on a planet).

Sean


On Wed, Jul 30, 2008 at 11:47 PM, Apptech <apptechspamBeGonespam.....paradise.net.nz> wrote:
> As one such lake is about as large as Lake Ontario (so now
> named "Ontario Lacus ") and is believed to be filled with
> liquid Ethane and Methane it may, one day, prove 'quite
> useful'. (Atmosphere is ~ 95% Nitrogen with a Methane liquid
> cycle and Ethane is formed from sunlight decomposition of
> Methane
>

2008\07\31@015600 by Apptech

face
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> Out of curiosity, I worked out how long the world's
> present energy
> consumption could be supplied by such a lake:

> At this rate, the lake would last 34 years. Not all that
> long!


That's just the largest lake that they are aware of. They
are scattered all over the planets surface AFAIK. After all,
it rains Methane there :-).


       Russell

'[TECH]:: Indexing mechanisms / Cycloidal gears / R'
2008\07\31@064700 by Apptech

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>From a private email to friends.

Immensely absorbing story of the Rootes Group (last
reference)
Be warned !!!!

Rest is OK too.

____________________

Indexing mechanisms

       http://www.roymech.co.uk/Useful_Tables/Cams_Springs/Indexing.html

Good cycloidal gears explanation

       http://mysite.du.edu/~etuttle/tech/cycloid.htm

  Interestingly, from above :

   Roots blower:     It was patented by the Roots brothers
in 1860 as a blast furnace blower, but was invented in 1848
by Isaiah Davis.

_______

Nothing to do with Roots - but highly interesting. Be warned
!!!!!!!!!!!!!!!!!!!!!

       http://en.wikipedia.org/wiki/Rootes

'[TECH] Now that is how I want to get to work ...'
2008\07\31@072856 by Matthew Rhys-Roberts

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I remember this, however it's not the thing I was thinking of... What I
remember seeing in book and film was a very large single rotor blade,
counterbalanced on the opposite side of the rotor shaft. I don't think
it ever flew, it just provided a lot of test data.

If anyone knows the make & model of such a thing I'd be grateful.

Thanks
Matt


Mark Huffstutter wrote:
{Quote hidden}

2008\07\31@085812 by Apptech

face
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>I remember this, however it's not the thing I was thinking
>of... What I
> remember seeing in book and film was a very large single
> rotor blade,
> counterbalanced on the opposite side of the rotor shaft. I
> don't think
> it ever flew, it just provided a lot of test data.

I'm going to have to start sending invoices, or stop reading
this stuff .... !!!! :-)

Gargoylegargoylegarglegarglegarglegagglegigglegoggle ....

Yee Haaaaaaaaaaaaaaaaa!!!

       http://home.att.net/~dannysoar2/Whirlygig.htm

It's a "Schraubenflieger"

But, then, so is this ...

       www.worldwar1aeroplanesinc.org/forums/showthread.php?t=384
       http://img186.imageshack.us/my.php?image=totaaltekeningfk5.jpg

More properly the single winger is "Schraubenflieger Papin
und Rouilly"

Here:
   http://translate.google.com/translate?hl=en&sl=de&u=http://www.jadu.de/luftfahrt/flugwesen/schraubenflugzeuge/schraubenflzg.html&sa=X&oi=translate&resnum=1&ct=result&prev=/search%3Fq%3Dschraubenflieger%2Bpapin%2Bund%2Brouilly%26num%3D100%26hl%3Den%26safe%3Doff%26sa%3DG

<Brain hurt mode on>

   " There are now more recently, two French, Papin and
Rouilly, in a very strange idea has come. Sie verwenden
ebenfalls eine großflügelige Hubschraube, aber sie verlegen
die Antriebskraft an deren Umfang statt in die Achse. They
also use a großflügelige Hubschraube, but they embarrassed
the driving force in their scope instead of the axis. das
erscheint recht sonderbar, ist aber tatsächlich dadurch zu
erreichen, daß sie den Flügel hohl bauen und einen Luftstrom
hindurchtreiben, den sie außen, wie bei dem bekannten
Segnerschen Wasserrad, nach rückwärts ableiten. this seems
quite odd, but in fact it is thus to ensure that the hollow
wing and build an air stream hindurchtreiben, it outside, as
in the famous Segnerschen water, to derive backward. Der
Rückdruck des austretenden Strahls treibt die flügel an. The
back pressure of the exiting beam pushes the flügel. Um den
Luftstrom zu erhalten, ist ein kräftiger Ventilator
eingebaut, der vom Flugzeugmotor angetrieben wird. In order
to maintain air flow, is a strong fan built by the aircraft
engine. Imdrehpunkt sitzt in Kugellagern eine Art Topf mit
einem Schwimmer; das ist der Führerraum. Imdrehpunkt sits in
a kind of ball bearings pot with a float, which is the
driver. damit dieser teil nicht von dem umlaufenden Flügel,
in dem er sitzt, mitgenommen wird, erhält er ein
röhrenförmiges Steuer, durch das ein Luftstom von solcher
Stärke getrieben wird, daß der Führersitz stillsteht und der
Flügel sich um ihn herumdreht. so that no part of the
pivoting wing, in which he sits, too, he will receive a tax
röhrenförmiges through which Luftstom of such strength takes
place, that the driver's seat and stopped the wings to him
herumdreht.
Ursprünglich hatten die Erfinder wie bei einem gewöhnlichen
Propeller zwei einander gegenüberliegende Flügel vorgesehen.
Initially, the inventor as a normal propeller two opposite
wing. Jetzt haben sie aber ein ganz eigentümliches Flugzeug
mit nur einem Flügel gebaut (siehe Abbildung) . Now, they
have but a very strange plane with only one wing built (see
illustration). Fast scheint es unmöglich, daß dieser Apparat
überhaupt fliegen könnte, da doch der Luftstützpunkt auf der
einen und das Hauptgewicht auf der anderen Seite liegt. It
seems almost impossible that this apparatus could ever fly,
but since the air base on the one hand and the emphasis on
the other side. Und doch zeigt eine schöpfung der Natur, daß
dieses Problem zu lösen ist. And it shows a creation of
nature that this problem be solved. Denn es gibt ein
geflügeltes Samenkorn, dasjenige der Sykomore, das ebenfalls
nur einen Flügel besitz und doch schnell herumwirbelnd in
stetigem ruhigen Fluge, vom Winde über weite Strecken
fortgetragen, sich zur Erde senkt. Because there is a winged
seed, that the Sykomore, which is also only a wing and
possession but quickly herumwirbelnd steady in quiet flights
by winds over long distances fortgetragen, lowers to the
ground.

Wie ist es wohl möglich, daß dieses Gebilde im Gleichgewicht
bleibt? How is it indeed possible that this structure
remains in balance? Nun, des Rätsels Lösung liegt in der
Zentrifugalkraft. Now, the puzzle solution lies in the
centrifugal force. Sehen wir uns einmal unser Flugzeug
genauer an, das diesem Samen nachgebildet ist. Let us even
closer look at our aircraft, that the seeds emulated. Auf
der einen Seite des Drehpunktes liegt der leichte Flügel,
auf der anderen in kürzerer Entfernung der schwere Motor. On
one side of the rotation point is the light wing, on the
other in a shorter distance between the heavy engine. Wenn
das Flugzeug auf dem Sitzschwimmer ruht, sind beide Lasten
ausgeglichen. If the plane on the seat rests swimmers, both
offset the expense. Läuft nun das ganze System rasch um, so
ziehen die Zentrifugalkräfte beider Massen so stark nach
außen, daß das Ganze etwa wie zwischen enorm starken
Gummibändern eingespannt schwebt. Runs now the whole system
quickly so the centrifugal pull of both masses as much to
the outside, that the whole thing about how to distinguish
between enormously strong elastic bands fixed floats. Wenn
dies der Fall wäre, so könnte man vergeblich versuchen, das
Flugzeug zum Kippen zu bringen; so wirkt also die
Zentrifugalkraft ähnlich wie beim Kreisel auch hier
stabilisierend. If this were the case, could be vain attempt
to tilt the plane to bring, so therefore the centrifugal
effect similar to the roundabout also stabilizing. Wenn
einmal der Motor versagt, so muß der Luftdruck das Flugzeug,
ähnlich wie bei dem Samen, in Drehung halten. Once the
engine failed, so the air pressure must be the aircraft,
similar to the seeds, in rotation. Ob aber der Übergang aus
dem einen Zustand in den anderen so glatt gelingen wird,
erscheint doch recht zweifelhaft. Whether but the transition
from one state to the other as smooth succeed, it will put
quite doubtful. "

</ ...>


2008\07\31@090908 by Apptech

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> More properly the single winger is "Schraubenflieger Papin
> und Rouilly"


Flying model (!)

       http://modelbox.free.fr/analyses/MS2002_10P/SCRH_Papin/index.html

"Flight" tests of original ... !!!!!!!!!!!!!!!!

   http://modelbox.free.fr/photoscopes/Papin_Phot/index.html


'[TECH] Automatic Directory Compare Software?'
2008\07\31@142540 by Nicola Perotto

picon face
Hi all,
I use the "Synchronize Dirs" command of Total Commander
http://www.totalcommander.com (trial available).
It works very well.
       Nic


Josh Koffman wrote:
{Quote hidden}


'[TECH] NASA - Antarctic was once much warmer'
2008\08\01@015315 by Apptech
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NASA    July 23, 2008

   "A new fossil discovery – the first of its kind from the
whole of the Antarctic continent- provides scientists with
new evidence to support the theory that the polar region was
once much warmer.

The discovery by an international team of scientists is
published today in Proceedings of the Royal Society B. It
involved researchers from the University of Leicester, North
Dakota State University, the British Geological Survey,
Queen Mary University of London, and Boston University.

       http://earthobservatory.nasa.gov/Newsroom/MediaAlerts/2008/2008072327313.html

...
"Notwithstanding the significance of the fossil
preservation, the presence of lake ostracods at this
latitude, 77 degrees south, is also of great note. Present
conditions in this Antarctic region show mean annual
temperatures of minus 25 degrees C. These are impossible
conditions to sustain a lake fauna with ostracods."

"The fossils therefore show that there has been a
substantial and very intense cooling of the Antarctic
climate after this time interval that is important for
tracking the development of the Antarctic icesheet – a key
factor in understanding the effects of global warming.

... "

_______________________



And all done with a straight face.





       Russell


'[TECH]:: NASA - Snapshot of past climate revelas n'
2008\08\01@015315 by Apptech

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   " NASA
July 28, 2008

SNAPSHOT OF PAST CLIMATE REVEALS NO ICE IN ANTARCTICA
MILLIONS OF YEARS AGO

A snapshot of New Zealand's climate 40 million years ago
reveals a greenhouse Earth, with warmer seas and little or
no ice in Antarctica, according to research published this
week in the journal Geology.

The study suggests that Antarctica at that time was yet to
develop extensive ice sheets. Back then, New Zealand was
about 1100 km further south, at the same latitude as the
southern tip of South America – so was closer to
Antarctica – but the researchers found that the water
temperature was 23-25 degrees C at the sea surface and 11-13
degrees C at the bottom.

"This is too warm to be the Antarctic water we know today,"
said Dr Catherine (Cat) Burgess from Cardiff University's
School of Earth and Ocean Sciences, and lead-author of the
paper. "And the seawater chemistry shows there was little or
no ice on the planet."


       http://earthobservatory.nasa.gov/Newsroom/MediaAlerts/2008/2008072827309.html

... "

___________________

Soon we'll be seeing pigs on ladders ...


       Russell

'[TECH]:: NASA - Typhoons bury tons of CO2 in ocean'
2008\08\01@021145 by Apptech

face
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NASA
July 23, 2008

   " A single typhoon in Taiwan buries as much carbon in
the ocean – in the form of sediment – as all the other rains
in that country all year long combined. That's the finding
of an Ohio State University study published in a recent
issue of the journal Geology.

The study –
the first ever to examine the chemistry of stream water and
sediments
that were being washed out to sea
while a typhoon was happening at full force –

will help scientists develop better models of global climate
change.

       http://earthobservatory.nasa.gov/Newsroom/MediaAlerts/2008/2008072327311.html

... "

___________________




               Russell

'[TECH]:: NASA - Amazon outflow found to capture CO'
2008\08\01@021148 by Apptech

face
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NASA
July 23, 2008

   " Nutrients washed out of the Amazon River are powering
huge amounts of previously unexpected plant life far out to
sea, thus trapping atmospheric carbon dioxide, according to
a new study.

Until now, the areas around the Amazon and other great
rivers had been thought to be emitting CO2, so the study may
affect climate scientists' calculations of how the
greenhouse gas acts.

The study appears in this week's Proceedings of the National
Academy of Sciences. http://www.pnas.org/
"This new understanding allows us to better think about how
carbon dioxide is cycled between the atmosphere and the
oceans, and how this might change in the future," said lead
author Ajit Subramaniam, a biological oceanographer at
Columbia University's Lamont-Doherty Earth Observatory.
Lamont is part of The Earth Institute.



... "



       http://earthobservatory.nasa.gov/Newsroom/MediaAlerts/2008/2008072327312.html

____________________



       Russell

'[TECH] Now that is how I want to get to work ...'
2008\08\01@072855 by Matthew Rhys-Roberts

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This looks absolutely bonkers and I love it.

My French isn't that brilliant... How the heck is such a thing
controlled? At all?!?

Matt


'[TECH]:: Nickel prices'
2008\08\01@083001 by Apptech

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Thought about EE
Thought about OT

I'm not a market price follower of any product normally.
This one happens to be of relevance to me as it affects NimH
battery prices (or should).
Will have relevance to many people here.
Interesting to see how "markets" play fast and loose with
our craft.

Fascinating (to me) to see the changes which have occurred
in the last months and years.

       http://www.kitcometals.com/charts/nickel_historical_large.html

1 year price drop is about 8/13.
We are actually almost back to a 5 year historical level
after a 4x increase starting about 2.5 years ago. I'm sure
there are excellent reasons why. I haven't found out why.

It would be a great shame if I should come to feel that this
and similar things were of relevance to me after all these
years ;-).



       Russell





'[TECH] Nickel prices'
2008\08\01@141937 by Vitaliy

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Apptech wrote:
> Will have relevance to many people here.
> Interesting to see how "markets" play fast and loose with
> our craft.

Why the double quotes? :)

{Quote hidden}

The graphs are actually an excellent example of basic economic principles at
work. :-) The price spike concides perfectly with the dip in warehouse
stocks levels.

I'm not sure exactly what happened, but it was either (A) increase in demand
(B) reduction in supply or (C) both. Let us know what you find out, Russell.
:)

Vitaliy

2008\08\01@145745 by sergio masci

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On Fri, 1 Aug 2008, Vitaliy wrote:

> I'm not sure exactly what happened, but it was either (A) increase in demand
> (B) reduction in supply or (C) both. Let us know what you find out, Russell.
> :)

You forgot (D) manipulation of the market

Regards
Sergio Masci

'[TECH]:: Nickel prices'
2008\08\01@161906 by Tony Smith

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> I'm not a market price follower of any product normally.
> This one happens to be of relevance to me as it affects NimH
> battery prices (or should).
> Will have relevance to many people here.
> Interesting to see how "markets" play fast and loose with our craft.
>
> Fascinating (to me) to see the changes which have occurred in
> the last months and years.
>
>         www.kitcometals.com/charts/nickel_historical_large.html
>
> 1 year price drop is about 8/13.
> We are actually almost back to a 5 year historical level
> after a 4x increase starting about 2.5 years ago. I'm sure
> there are excellent reasons why. I haven't found out why.
>
> It would be a great shame if I should come to feel that this
> and similar things were of relevance to me after all these years ;-).


Maybe China is shutting down for a while while the Olympics are on.

Nah.

2/3rds of nickel goes towards stainless steel (the good 3xx stuff, not the
4xx they put on your fridge or makes spoons out of).  Ni-xxx batteries are
small change.

The price went up due to increased demand for stainless steel, various
nickel producers not getting their acts together and herd mentality.  Now
the opposite has happened, so the price is going down.  It's not expected to
back up anytime soon.  Many users of stainless steel have either switched
varieties, or accepted versions with less nickel.

At one of my jobs I get a daily email showing commodity prices with
anaylsis.  I'm not sure why I get it, but it's rather fascinating at times.
This price crash was supposed to happen, it's been predicted since the start
of the year.  I haven't been there for a few months, but will be next week.
I should check my mail to see if there's anything interesting.

Tony


'[TECH]:: Books, free, classics, zillions'
2008\08\01@194929 by Apptech

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Books from ~ 100 authors

       http://www.readprint.com/

Even Tarzan stories :-)
(Along with 20+ other ERB stories)

Authors as diverse as Sun Tzu, Bram Stoker, Machiavelli,
Donne, Tolstoy, Virgil, Voltaire, ... .

______________________________

George Orwell's essays and short pieces are worth reading.

   http://www.readprint.com/author-66/George-Orwell

On Ghandi
http://www.readprint.com/work-1260/George-Orwell

On Spain towards the end of the Spanish Civil War ,
September 1937.
What Orwell saw in Spain disillusioned him re the extreme
versions of socialism and led to "Animal Farm" and "1984".

           http://www.readprint.com/work-1255/George-Orwell

       Russell




'[TECH] Nickel prices'
2008\08\02@003207 by Vitaliy

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sergio masci wrote:
>> I'm not sure exactly what happened, but it was either (A) increase in
>> demand
>> (B) reduction in supply or (C) both. Let us know what you find out,
>> Russell.
>> :)
>
> You forgot (D) manipulation of the market

Which is a special case of (B). :)

For a commodity like nickel, extremely unlikely (also supported by Tony
Smith's explanation).

2008\08\02@032454 by Tony Smith

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> sergio masci wrote:
> >> I'm not sure exactly what happened, but it was either (A)
> increase in
> >> demand
> >> (B) reduction in supply or (C) both. Let us know what you
> find out,
> >> Russell.
> >> :)
> >
> > You forgot (D) manipulation of the market
>
> Which is a special case of (B). :)


B & D are indeed related.

BHP in Australia shut down a plant a few months ago, causing a rise in
prices.  Although there are many nickel suppliers worldwide, you could still
rig the market as supply is tight.  It doesn't really work for some other
metals, eg gold, as it's essentially a useless metal.  The Australian
Goverenment once did the opposite, it dumped a lot of gold, making the price
drop.

Another reason nickel prices are falling is due to second sourcing, since
the price has been high enough for long enough, low yield areas (Asia) are
coming on-line.  It's a bit like when oil prices go up, people start taking
about mining shale oil.  That never seems to happen though.

Tony

'[TECH]Solar energy news from MIT'
2008\08\02@174450 by cdb

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web.mit.edu/newsoffice/2008/oxygen-0731.html
--
cdb,   3/08/2008

--




spam_OUTcolinspamKILLspambtech-online.co.uk

2008\08\02@181046 by Byron Jeff

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On Sat, Aug 02, 2008 at 05:45:03PM -0400, cdb wrote:
>  http://web.mit.edu/newsoffice/2008/oxygen-0731.html

In summary it's a new process for water splitting into H2 and O2.
The huge question is what is the efficiency? If you put one kW of
electricity into the process, how much energy can be produced from the
resulting hydrogen and oxygen?

Also there's still issues on hydrogen storage to be addressed. You can't
just contain it like air.

Waiting for more data.

BAJ

2008\08\02@222430 by Apptech

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> On Sat, Aug 02, 2008 at 05:45:03PM -0400, cdb wrote:
>>  http://web.mit.edu/newsoffice/2008/oxygen-0731.html


> In summary it's a new process for water splitting into H2
> and O2.
> The huge question is what is the efficiency? If you put
> one kW of
> electricity into the process, how much energy can be
> produced from the
> resulting hydrogen and oxygen?

I meant to post on this a few days ago but didn't.
It was an embargoed release out on 31 July so they seemed to
think it significant.

The key issues the new process is said to address are
covered in the press releases.

Essentially (they say), until now electrolysis had good
efficiency as far as the Hydrogen side of the cell as the
available catalysts worked well BUT the Oxygen generation
was inefficient due to the cell potential needed being
higher than the theoretical half-cell potential.

What they have done is come up with an Oxygen generation
catalyst which allopws nearly 100% of theoretical efficincy
so that Hydrogen generation is now very close to 100%
efficient. This is a very timely response to the issue that
I addressed recently - I noted that there was no theoretical
reason that conversion could not be almost 100% but that
this had not yet been achieved in practice. Apparently it
now has, so we can (perhaps) move on to the other issues.

> Also there's still issues on hydrogen storage to be
> addressed.
> You can't
> just contain it like air.

True. But air is harder to burn :-).

> Waiting for more data.

Granted -

Storage is being addressed extensively and intensively as
per other recent posts.
US energy department Hydrogen "storage in a solid" targets
were 6.5% by mass.

That's a pathetic 1.6 kWh/kg.
But about 5 times (falling with new developments) the mass
density of Lithium Ion batteries.
IF you eg used the Hydrogen to run a heat engine (IC or
Stirling or ...) you'd likely still be noticeably ahead of
Li Ion overall on energy mass density.


>From before:

"For now" here is an article by people who think that
Hydrogen may be a potentially viable energy transfer media.

   http://www.rsc.org/Education/EiC/issues/2007Nov/FuellingFutureSolidPhaseHydrogenStorage.asp

They point out the difficulties and the storage goal - which
is modest if achieved and may not be achievable. ie 6.5%
Hydrogen storage by mass in "solid phase" storage (hydrides
or nanotubes ??? ...).

AND:

These people are claiming a quantum leap to 720 W/kg (they
asy 720W/kg but I'll assume that's just a typo and not
ignorance)

       http://www.everspring.net/txt/product-battery.htm?gclid=CPT0463h6ZQCFRIuagod1yigQQ


AND


Note that LiPo here is only talking about around 200 Wh/kg.
   http://en.wikipedia.org/wiki/Lithium-polymer
LiIon with < 200 here
   http://www.batteryuniversity.com/partone-3.htm



       Russell

'[TECH]:: Books, free, classics, zillions'
2008\08\02@224617 by Martin K

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www.gutenberg.org/


Apptech wrote:
{Quote hidden}

'[TECH]:: SPACEX Falcon 1 launch failure'
2008\08\03@023611 by Apptech

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SpaceX's 3rd Falcon-1 orbital launch attempt from Kwajalein
Atoll failed today about 2+ minutes into the flight.

Elon Musk says that the problem was failure for the first
stage to separate. The second stage fired on schedule and
...


       http://www.spaceref.com:80/news/viewnews.html?id=1299



       Russell


'[TECH]Solar energy news from MIT'
2008\08\03@031020 by Cedric Chang

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That was one of the most poorly written releases I have seen.  And  
where do they come up with those silly, " it will take 10 years to  
commercialize".  As if they have any idea whatsoever.
cc



'[TECH]:: Hottest water on earth's "surface"'
2008\08\04@095920 by Apptech

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470 degrees C in open vents above a (presumed) magma dome at
> 3000 metres deep on the mid Atlantic ridge. Water is
supercritical at these temperatures and pressures.

       http://environment.newscientist.com/article/dn14456


   Russell McMahon

'[TECH]:: How to make a ... (mainly platic related)'
2008\08\04@105744 by Apptech

face
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Tap Plastics "How to make a ..." instructional video series.

       http://www.tapplastics.com/info/video.php#video22

No doubt they'd like you to use their products where
relevant :-)


             Russell



       Introduction to TAP Mold Making Products
       How to build a Mold Box
       How to make a Latex Mold
       How to make a Urethane Mold
       How to make a simple Silicone Mold Part 1
       How to make a simple Silicone Mold Part 2
       How to build a Plastic Heat Bender
       How to bend Plastic
       How to apply Window Film
       How to select Window Film
       How to apply Vinyl Graphics
       How to cut Plastic Sheet
       How to use Ultra-Glo and Ultra-Seal
       How to glue Acrylic
       Cast embedments in Clear Resin
       How to make a two-part mold
       How to repair scratched CDs, DVDs, iPods and more
       How to repair Gelcoat Part 1
       How to repair Gelcoat Part 2
       How to repair and glue Polyethylene and Seaboard
       How to protect your LCD or DLP TV
       How to build a Box with Plastic

'[TECH]Solar energy news from MIT'
2008\08\04@125328 by piclist

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On Sun, 3 Aug 2008, Apptech wrote:
> Storage is being addressed extensively and intensively as
> per other recent posts.
> US energy department Hydrogen "storage in a solid" targets
> were 6.5% by mass.

Still not good enough for a car.. but what this is really going to do is
make solar and wind much more viable.

If you can cover your roof with solar, and have a washing machine sized
box in your basement that converts spare power in the day into hydrogen
and oxygen, then burns it later when it's needed.  Or a much larger
version for huge solar arrays that can provide power on demand at night.

--
Ian Smith
http://www.ian.org

2008\08\04@132357 by Apptech

face
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>> US energy department Hydrogen "storage in a solid"
>> targets
>> were 6.5% by mass.

> Still not good enough for a car.

Maybe not. But Lotus will sell you a Li Ion battery powered
car with even lower mass energy density and a $100,000 price
tag, and tell you how wonderful it is.

{Quote hidden}

Or a larger water gasometer at near atmospheric pressure
that uses off peak mains from whatever source to do water
electrolysis at near 100% efficiency, and the hydrogen is
burned next day.


   R


'[TECH]:: How to make a ... (mainly platic related)'
2008\08\04@134752 by piclist

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On Tue, 5 Aug 2008, Apptech wrote:
> Tap Plastics "How to make a ..." instructional video series.
>
>         www.tapplastics.com/info/video.php#video22
>
> No doubt they'd like you to use their products where
> relevant :-)

TAP Plastics is an awesome shop.  I have one locally which I visit quite
often for supplies.  Good prices too.

One of my hobbies is working with acrylic.  What I like about the stuff is
that you don't glue pieces together.  You place two bits together and
inject a solvent between them and it unbinds the long chain molecules,
lets them mingle and then evaporates.  You wind up with a seamless (with
practice) join that makes the two parts one solid piece.

--
Ian Smith
http://www.ian.org

'[TECH]:: How to make a ... (mainly plastic related'
2008\08\04@141049 by Bob Blick

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On Mon, 4 Aug 2008 13:47:28 -0400 (EDT), RemoveMEpiclistRemoveMEspamEraseMEian.org said:

> One of my hobbies is working with acrylic.  What I like about the stuff
> is
> that you don't glue pieces together.  You place two bits together and
> inject a solvent between them and it unbinds the long chain molecules,
> lets them mingle and then evaporates.  You wind up with a seamless (with
> practice) join that makes the two parts one solid piece.

The only problem is the evaporation part - I hate grabbing the can and
finding it empty, when it was half full last time I used it!

TAP plastics is fun, I have one on my commute route and it's fun to
browse in the $0.10 bin.

Cheerful regards,

Bob


--
http://www.fastmail.fm - And now for something completely different…

2008\08\04@144227 by piclist

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On Mon, 4 Aug 2008, Bob Blick wrote:
> The only problem is the evaporation part - I hate grabbing the can and
> finding it empty, when it was half full last time I used it!

Oh yeah.. and the fact it's insanely toxic and you shouldn't touch it or
breathe the fumes.

--
Ian Smith
http://www.ian.org

2008\08\04@160930 by John Ferrell

face picon face
What is the solvent?

John Ferrell    W8CCW

"All that is necessary for the triumph of evil is for good men to do
nothing." -- Edmund Burke
http://DixieNC.US

{Original Message removed}

2008\08\04@162238 by Bob Blick

face
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>From the can, which smells nasty even when screwed tightly shut:

"Contains Methylene Chloride, Trichloroethylene and Methyl Methacrylate
Monomer"

-Bob

On Mon, 4 Aug 2008 16:09:29 -0400, "John Ferrell"
<KILLspamjohnferrellspamspamBeGoneearthlink.net> said:
> What is the solvent?
>
> John Ferrell    W8CCW
>
> "All that is necessary for the triumph of evil is for good men to do
> nothing." -- Edmund Burke
> http://DixieNC.US
>
> {Original Message removed}

2008\08\04@181016 by Apptech

face
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> >From the can, which smells nasty even when screwed
> >tightly shut:
>
> "Contains Methylene Chloride, Trichloroethylene and Methyl
> Methacrylate
> Monomer"

Methylene Chloride is a known (ie generally claimed)
carcinogen.

Trichloroethylene th same, plus for good measure a liver
poison absorbed through the skin. We used to splash it
around for cleaning and it was a standard dry cleaning fluid
for many years.

MM my brain has no comments on (no doubt Gargoyle has) , but
I've no doubt  it will be a match for the other two as well
:-).

Stand clear - preferably up wind.

This is almost certainly typical

       http://selectproducts.com/ftpfiles/weld4.pdf

Says:

This material is an aspiration hazard and defats the skin.
The ingredients are toxic by inhalation and ingestion and
may be absorbed through the skin. Exposure by these routes
may cause central nervous system depression, liver and
kidney damage and may sensitize the heart muscle. Methylene
Chloride may interfere with the oxygen carrying capacity of
the blood. Methylene Chloride and Trichloroethylene are
possible human cancer hazards based on test results with
laboratory animals. Methylene Chloride has been listed as a
potential carcinogen by IARC and NTP. Trichloroethylene has
not been identifed as a carcinogen by IARC, NTP, ACGIH or
OSHA. Methylene Chloride is not believed to pose a
measureable risk to man when handled as recommended.  Under
some circumstances, mutagenic changes have been observed
with Methyl Methacrylate in animal studies. Precautions
should be taken to avoid unnecessary exposure to this
cement.


YMMV.
But YMMNV.


____________

       http://msds.chem.ox.ac.uk/ME/methyl_methacrylate.html




       Russell



'[TECH] Is Winglet the Segway killer?'
2008\08\04@183352 by Jinx

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Toyota has developed a motorised, stand-up-and-ride scooter
designed to help people dash around at malls and airports

http://www.nzherald.co.nz/section/story.cfm?c_id=5&objectid=10525229


http://en.wikipedia.org/wiki/Segway_PT

"Segway's Breakdown"

http://www.wired.com/wired/archive/11.03/segway.html

2008\08\04@191517 by Brendan Gillatt

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-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Jinx wrote:
{Quote hidden}

I have to say, aside from the odd red paint job, I would feel far less
self-conscious on a Winglet than on a Segway. Besides, being able to use
it hands free would make it more practical. If the price is right I might
even be tempted to buy one; there is not chance of me buying a Segway.
Not for at its current price.

- --
Brendan Gillatt | GPG Key: 0xBF6A0D94
brendan {a} brendangillatt (dot) co (dot) uk
http://www.brendangillatt.co.uk
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'[TECH] Canon HF100 camcorder (was: [EE] SDHC Cards'
2008\08\04@195759 by Vitaliy

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Carlos Marcano wrote:
> So, Adam, how has this nice looking camera been doing?

Yeah, you promised to tell us more! :)

'[TECH]:: How to make a ... (mainly platic related)'
2008\08\04@201935 by Vitaliy

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Apptech wrote:
> Tap Plastics "How to make a ..." instructional video series.
>
>        http://www.tapplastics.com/info/video.php#video22
>

Superb stuff.

I really like the videos: they are simple, but to the point, and obviously
professionally made. Once we started working on our own training videos, I
began noticing this kind of stuff. :)

Vitaliy

'[TECH] Is Winglet the Segway killer?'
2008\08\04@203956 by Vitaliy

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Jinx wrote:
> "Segway's Breakdown"
>
> http://www.wired.com/wired/archive/11.03/segway.html

There's no argument that Segway is a great invention, but the price is too
high, and the marketing is poor (sounds like they're being too careful).

How much would you guess it costs to build a Segway (if you don't count the
overhead)?

Vitaliy

'[TECH]:: Comments on trends in patent filings'
2008\08\04@214547 by Apptech

face
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Interesting if only somewhat useful.

       http://www.nzherald.co.nz/section/story.cfm?c_id=5&objectid=10524727

US highest filing volume.
2.5 year backlog.
Japanese are top filers.
US 400,000+ applications pa of which ~= 50% from US sources.

   R

'[TECH] Billiard physics and related information <-'
2008\08\04@214548 by Apptech

face
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This sort of thing is very appropriate to [TECH].

> not sure who here is interested in pool/billiards etc.,
> but even if you're
> not, this fascinating website might be of interest to you:
> http://billiards.colostate.edu/  Many calculations,
> explanations and
> demonstrations of effects seen in pool, some with normal
> or high speed
> video. Highly recommended!
> Regards,
> - Marcel

'[TECH] Canon HF100 camcorder (was: [EE] SDHC Cards'
2008\08\04@233426 by M. Adam Davis

face picon face
Aaugh, I'm being mobbed by piclisters!  ;-D

I delayed as I haven't had time to fiddle with the actual files
produced yet.  The software included is, for all intents and purposes,
useless (on the video end - the pictures are managed by the same
software Canon uses with their SLRs, which is very good for what I
need).  I'm going to be looking at a few packages over the next week
or two, but AVCHD is still a new format for HD video.  I complicate
matters further by using a Windows Vista 64 system as my main machine
- Sony's video editing software, for example, installs but then
crashes on startup.  I still have 3-4 more AVCHD editing packages to
try out, and expect I'll find something suitable this week.

For now I'm using my XP laptop to transfer the video to an external
HD.  The laptop is not a speed demon, though, so I'm no going to
attempt to edit video on it.  The included software doesn't download
on my Vista 64 system - it loads, and downloads smaller videos (50MB
or less) but fails on larger videos.  I imagine it's a driver issue
Canon will eventually clear up, but as I'm saving them to an external
drive anyway it doesn't matter which computer I use, so for now I'm
using an XP system to take the video from the camera.  The file format
on the SD cards is not what you get on the PC, though, so at the
moment I do have to transfer from the camera rather than an SD reader.
It looks like a bunch of transport streams and a bunch of files with
meta information, and the included software probably grabs the
necesary files and stitches them together during the transfer.

The latest nightly build of VLC (VideoLanClient) plays the raw M2TS
files just fine, and I expect I can use it to transcode (and I've seen
messages online saying ffmpeg works with AVCHD M2TS files now) so I
don't expect it to be a roadblock, but I do wish the included software
had more features, especially regarding transcoding the video to a
standard mpeg4 AVI.

I'm told that for 32 bit XP and Vista users, there are several good
editing programs available that work out of the box - I'm running a
non-standard setup.

As far as the camcorder itself -
- Battery life is as good/poor as described (about an hour on highest
quality, 90 minutes on lower quality).  I purchased a second regular
battery and an external charger.  I might get the extended battery
later, or wait for a quality generic to become available.
- Video quality from the camcorder to an HD monitor is VERY good
using component out.
- Audio quality is better than I expected - certainly good enough for
most usage.  Not noisy, picks up quiet sounds easily and clearly
(small children speaking quietly).  I'm pleased with it.  Haven't
tested for stereo seperation.
- Low light performance is good - recorded a stage play from a few
rows back, colors, etc were good.  Could detect a slight graininess of
the video.  Pointing away from the stage into the darkened audience
and you lose most color while the 'grain' becomes very noticable, but
everything is discernable.
- I do wish it was wider on the wide angle end - I found myself
backing up in small rooms to get the view I wanted.  There's a wide
angle lens available, but I don't want the wider view so badly that
I'm willing to spend $100+ on it.
- Contrary to published reports I had no problems slipping the
camcorder into my shirt pockets and pants pockets.  It fit very nicely
and I had no worries about it falling out - it goes completely inside.
I'm probably going to buy a plain glass filter for it so I don't have
to worry about dust or scratches on the lens from having it hit other
items in my pockets - the front lens cover is held closed by springs,
and opens easily if touched from the front.
- The still camera images are good - I'm used to the Canon XTi DSLR
which is noticably better, but it was good enough that I didn't carry
the slr around with me on a recent vacation and instead used the
camcorder - better than the point and shoot's I've used in the past.
Now that I think about it, I have a sample:
http://flickr.com/photos/adavis/2734495254/ Exif:
flickr.com/photos/adavis/2734495254/meta/
- I'm still very surprised at the macro capabilities.  Really very
nice.  Combined with the zoom I wish I had the camcorder with me
rather than the SLR on a recent visit to a buterfly house.  I couldn't
get a great picture of a flying blue morpho, but I suspect a still HD
video frame would have been better than what I did capture.

So, the only issue I have right now is that I don't have a good video
software workflow.  Having not owned a camcorder before, and having
heard from friends that most camcorders don't come with good software
I wasn't expecting to have this set up quickly anyway, but I do wish
the software had enough functionality to convert to something that
Vimeo or Youtube can eat.

I'm planning on taping the next Go Tech meeting (Ann Arbor local
maker/electronics/computers/CNC/robots/etc enthusiast group) next
Tuesday, so I expect a few days after that I'll have some video
online, and I'll see about putting some of the raw stuff up so you can
see what it produces.  Hopefully I'll have a workflow setup by then
that requires almost no effort to go from camera to HD Vimeo online.

Let me know if you have any questions or want me to try something with it...

-Adam

On Mon, Aug 4, 2008 at 7:54 PM, Vitaliy <spamspamspammaksimov.org> wrote:
> Carlos Marcano wrote:
>> So, Adam, how has this nice looking camera been doing?
>
> Yeah, you promised to tell us more! :)
> -

2008\08\05@073052 by olin piclist

face picon face
Vitaliy wrote:
>> So, Adam, how has this nice looking camera been doing?
>
> Yeah, you promised to tell us more! :)

I'm not Adam (whoever that is), but I got my son a HF100 for birthday and
highschool graduation.  I'm impressed with the camera itself.  Two hours of
HD video at the highest quality setting on a 16Mb card is fine.  The image
quality is good too, although you can sometimes still see compression
artifacts when there is lots of motion.  The highest quality setting is
17Mbits/second.

This is a rapidly advancing field, so I'm sure there will be something
better out in 6 months, but the HF100 looks like the best tradeoff for a
affordable personal HD video camera today.

The problem is the video editing software.  The stuff that comes with the
camera is way too slow unless maybe you have a top of the line fully souped
up desktop system.  It was unusable on my son's laptop.  We got the Ulead
video editing software ($80 download).  It works on smaller systems because
it has what they call a "proxy" mode.  The high res HD is essentially
precomputed into low res that you do the editing with, then the final result
is of course rendered from the original high res HD.

The Pinnacle software was the other contender, but it wasn't clear whether
they had anything like this proxy mode and there was no free trial, so we
got the Ulead software and are happy with it.  You do need the Ulead version
11.5, not 11.0.  Version 11.5 adds support for importing the ADVCHD
(something like that) files the HF100 camera creates.  Version 11.0 can't.
You end up buying 11.0, despite what the screen says when you click BUY NOW,
then you have to add the free upgrade to 11.5 separately.  They could have
made that easier and less confusing, but after the initial hassle all works
as expected.


********************************************************************
Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
(978) 742-9014.  Gold level PIC consultants since 2000.

2008\08\05@080626 by fred jones

picon face

I hang out on the hv20.com forum site where many of the guys are professionals.  Because of their dissatisfaction with AVCHD (first gen anyway), I decided to go with the HV30 instead of the HF100.  Of course it is a fantastic little camcorder, the number 1 rated HD consumer camcorder just barely beating out Sony.  My coworker got the HF100 recently and now I'm not so sure I made the right choice.  I wanted the best quality I could get so I decided to go with tape one more time.  After seeing the quality and convenience of his HF100, I think it may have been worth a slightly lower video quality.  Oh well, what's done is done.
FJ> Date: Mon, 4 Aug 2008 23:34:21 -0400> From: RemoveMEstienmanspamBeGonespamRemoveMEgmail.com> To: KILLspampiclistspamBeGonespammit.edu> Subject: Re: [TECH] Canon HF100 camcorder (was: [EE] SDHC Cards, was Re: Digital Sound)> > Aaugh, I'm being mobbed by piclisters! ;-D> > I delayed as I haven't had time to fiddle with the actual files> produced yet. The software included is, for all intents and purposes,> useless (on the video end - the pictures are managed by the same> software Canon uses with their SLRs, which is very good for what I> need). I'm going to be looking at a few packages over the next week> or two, but AVCHD is still a new format for HD video. I complicate> matters further by using a Windows Vista 64 system as my main machine> - Sony's video editing software, for example, installs but then> crashes on startup. I still have 3-4 more AVCHD editing packages to> try out, and expect I'll find something suitable this week.> > For now I'm using my XP laptop to transfer the video to an external> HD. The laptop is n!
ot a speed demon, though, so I'm no going to> attempt to edit video on it. The included software doesn't download> on my Vista 64 system - it loads, and downloads smaller videos (50MB> or less) but fails on larger videos. I imagine it's a driver issue> Canon will eventually clear up, but as I'm saving them to an external> drive anyway it doesn't matter which computer I use, so for now I'm> using an XP system to take the video from the camera. The file format> on the SD cards is not what you get on the PC, though, so at the> moment I do have to transfer from the camera rather than an SD reader.> It looks like a bunch of transport streams and a bunch of files with> meta information, and the included software probably grabs the> necesary files and stitches them together during the transfer.> > The latest nightly build of VLC (VideoLanClient) plays the raw M2TS> files just fine, and I expect I can use it to transcode (and I've seen> messages online saying ffmpeg works with AVCH!
D M2TS files now) so I> don't expect it to be a roadblock, but I do wi
sh the included software> had more features, especially regarding transcoding the video to a> standard mpeg4 AVI.> > I'm told that for 32 bit XP and Vista users, there are several good> editing programs available that work out of the box - I'm running a> non-standard setup.> > As far as the camcorder itself -> - Battery life is as good/poor as described (about an hour on highest> quality, 90 minutes on lower quality). I purchased a second regular> battery and an external charger. I might get the extended battery> later, or wait for a quality generic to become available.> - Video quality from the camcorder to an HD monitor is VERY good> using component out.> - Audio quality is better than I expected - certainly good enough for> most usage. Not noisy, picks up quiet sounds easily and clearly> (small children speaking quietly). I'm pleased with it. Haven't> tested for stereo seperation.> - Low light performance is good - recorded a stage play from a few> rows back, colors, etc !
were good. Could detect a slight graininess of> the video. Pointing away from the stage into the darkened audience> and you lose most color while the 'grain' becomes very noticable, but> everything is discernable.> - I do wish it was wider on the wide angle end - I found myself> backing up in small rooms to get the view I wanted. There's a wide> angle lens available, but I don't want the wider view so badly that> I'm willing to spend $100+ on it.> - Contrary to published reports I had no problems slipping the> camcorder into my shirt pockets and pants pockets. It fit very nicely> and I had no worries about it falling out - it goes completely inside.> I'm probably going to buy a plain glass filter for it so I don't have> to worry about dust or scratches on the lens from having it hit other> items in my pockets - the front lens cover is held closed by springs,> and opens easily if touched from the front.> - The still camera images are good - I'm used to the Canon XTi DSLR> wh!
ich is noticably better, but it was good enough that I didn't carry> t
he slr around with me on a recent vacation and instead used the> camcorder - better than the point and shoot's I've used in the past.> Now that I think about it, I have a sample:> http://flickr.com/photos/adavis/2734495254/ Exif:> http://flickr.com/photos/adavis/2734495254/meta/> - I'm still very surprised at the macro capabilities. Really very> nice. Combined with the zoom I wish I had the camcorder with me> rather than the SLR on a recent visit to a buterfly house. I couldn't> get a great picture of a flying blue morpho, but I suspect a still HD> video frame would have been better than what I did capture.> > So, the only issue I have right now is that I don't have a good video> software workflow. Having not owned a camcorder before, and having> heard from friends that most camcorders don't come with good software> I wasn't expecting to have this set up quickly anyway, but I do wish> the software had enough functionality to convert to something that> Vimeo or Youtube can ea!
t.> > I'm planning on taping the next Go Tech meeting (Ann Arbor local> maker/electronics/computers/CNC/robots/etc enthusiast group) next> Tuesday, so I expect a few days after that I'll have some video> online, and I'll see about putting some of the raw stuff up so you can> see what it produces. Hopefully I'll have a workflow setup by then> that requires almost no effort to go from camera to HD Vimeo online.> > Let me know if you have any questions or want me to try something with it...> > -Adam> > On Mon, Aug 4, 2008 at 7:54 PM, Vitaliy <@spam@spamSTOPspamspam@spam@maksimov.org> wrote:> > Carlos Marcano wrote:> >> So, Adam, how has this nice looking camera been doing?> >> > Yeah, you promised to tell us more! :)> > -

2008\08\05@083329 by Apptech

face
flavicon
face
> I'm not Adam (whoever that is), but I got my son a HF100
> for birthday and
> highschool graduation.  I'm impressed with the camera
> itself.  Two hours of
> HD video at the highest quality setting on a 16Mb card is
> fine.  The image
> quality is good too, although you can sometimes still see
> compression
> artifacts when there is lots of motion.  The highest
> quality setting is
> 17Mbits/second.

It's stunning the compression rates that can be achieved
these days. :-)


       R

2008\08\05@094407 by Spehro Pefhany

picon face
Quoting Apptech <apptechspamBeGonespamspamBeGoneparadise.net.nz>:

>> I'm not Adam (whoever that is), but I got my son a HF100
>> for birthday and
>> highschool graduation.  I'm impressed with the camera
>> itself.  Two hours of
>> HD video at the highest quality setting on a 16Mb card is
>> fine.  The image
>> quality is good too, although you can sometimes still see
>> compression
>> artifacts when there is lots of motion.  The highest
>> quality setting is
>> 17Mbits/second.
>
> It's stunning the compression rates that can be achieved
> these days. :-)
>
>
>         R

Meanie. I was wondering what would happen if I put an 8MB CF card up  
on eBay...

Best regards,
Spehro Pefhany
--
"it's the network..."                          "The Journey is the reward"
spamBeGones...spaminterlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

2008\08\05@095432 by M. Adam Davis

face picon face
On 8/5/08, Apptech <spam_OUTapptechSTOPspamspamparadise.net.nz> wrote:
> It's stunning the compression rates that can be achieved
> these days. :-)

Wait until we get 3D object recognition in real time in the camcorder
- then all they'll do is record 3D meshes with textures moving about
the scene.  15:1 is nothing!

;-D

-Adam

--
EARTH DAY 2008
Tuesday April 22
Save Money * Save Oil * Save Lives * Save the Planet
http://www.driveslowly.org

2008\08\05@102047 by Apptech

face
flavicon
face
>> It's stunning the compression rates that can be achieved
>> these days. :-)

> Wait until we get 3D object recognition in real time in
> the camcorder
> - then all they'll do is record 3D meshes with textures
> moving about
> the scene.  15:1 is nothing!

15:1???
Nay sir

> I'm impressed with the camera itself.
> Two hours of HD video at the highest
> quality setting on a 16Mb card is
> fine.  ...
>  The highest
> quality setting is 17Mbits/second.

17 Mb/s x 1/8 Bytes x 7200 seconds / 16 MB ~= 956:1*

:-)

FWIW 17 /8*7200 = 15.3 GB or NO compression at all.
Or, maybe that's unwinding the calculation that produced the
17 Mb/s in the 1st place.
Seems quite likely. Full circle ;-).



       Russell

That 956 = 1000 for some values of = is not a coincidence
:-)





2008\08\05@104036 by M. Adam Davis

face picon face
heh heh heh, I missed the Mb vs GB discrepancy.

-Adam

On 8/5/08, Apptech <RemoveMEapptechspamspamparadise.net.nz> wrote:
{Quote hidden}

> -

2008\08\05@121925 by olin piclist

face picon face
Apptech wrote:
> 17 Mb/s x 1/8 Bytes x 7200 seconds / 16 MB ~= 956:1*

You slipped a few decimal points.  HD video is 1920 x 1080 pixels per frame,
which is 2.1 Mbyte.  With interlacing (1080i at 60Hz format) you send half
that 60 times per second for a total uncompressed data rate of 62.6
Mbyte/sec or 498 Mbit/sec.  498/17 = about 30:1 compression.

Two hours of 17 Mbit/sec is 15.3 Gbytes, which makes the claim of 2 hours
recording time on a 16 Gbyte card seem plausible.


********************************************************************
Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
(978) 742-9014.  Gold level PIC consultants since 2000.

'[TECH] Helmholtz coil manufacturers'
2008\08\05@124129 by Jonathan Hallameyer

picon face
Hello All,
I'm looking to buy a tri-axis helmholtz coil system and having a bit
of difficulty finding manufacturers of such systems with google, The
Ive found a couple, but the majority of the results are technical
papers and links to patent sites. Anyone know of any manufacuturers,
or a better search engine to use? Ive tried globalspec but that
returns nothing at all for "helmholtz"

Thanks,
Jonathan Hallameyer

'[TECH] Canon HF100 camcorder (was: [EE] SDHC Cards'
2008\08\05@125633 by Spehro Pefhany

picon face
Quoting Olin Lathrop <TakeThisOuTolin_piclistspamspamRemoveMEembedinc.com>:

> Apptech wrote:
>> 17 Mb/s x 1/8 Bytes x 7200 seconds / 16 MB ~= 956:1*
>
> You slipped a few decimal points.  HD video is 1920 x 1080 pixels per frame,
> which is 2.1 Mbyte.

With no compression or chroma subsampling there are 3 bytes per pixel.

{Quote hidden}

> -

'[TECH] Helmholtz coil manufacturers'
2008\08\05@130003 by M. Adam Davis

face picon face
A google search

http://www.google.com/search?q=helmholtz+coil+three+axis

Brings up two manufacturers on the first page:

http://www.meda.com/Data_Sheets/hcs01.pdf

http://www.laboratorio.elettrofisico.com/eng/products.asp?famiglia=Instrumentation&sottofamiglia=HELMHOLTZ%20COILS

Looks like the larger fields are custom designs, but perhaps the
smaller fields available in the second link are "off the shelf" items.

-Adam

On 8/5/08, Jonathan Hallameyer <KILLspamjmhtauspamspamspam_OUTgmail.com> wrote:
> Hello All,
> I'm looking to buy a tri-axis helmholtz coil system and having a bit
> of difficulty finding manufacturers of such systems with google, The
> Ive found a couple, but the majority of the results are technical
> papers and links to patent sites. Anyone know of any manufacuturers,
> or a better search engine to use? Ive tried globalspec but that
> returns nothing at all for "helmholtz"
>
> Thanks,
> Jonathan Hallameyer
> -

'[TECH]:: How to make a ... (mainly plastic related'
2008\08\05@131458 by Al Shinn

picon face
Now THAT was a really clever bit no doubt from their marketing dept -
That solvent cement used to be supplied in little glass bottles - I
still have a couple of them from probably more than ten years ago -
still half full! Still works fine! AND, way easier to open with my POOR
old arthritic hands (whine)!
The story when I asked about the horrible self emptying cans was that
there was too much breakage with the LITTLE glass bottles and besides,
the stuff goes bad after awhile anyway. Yeah, right!

--

Looking forward,
Al Shinn

On Mon, 4 Aug 2008, Bob Blick wrote:
>The only problem is the evaporation part - I hate grabbing the can
>and finding it empty, when it was half full last time I used it!



'[TECH] Canon HF100 camcorder (was: [EE] SDHC Cards'
2008\08\05@132757 by olin piclist

face picon face
Spehro Pefhany wrote:
>> HD video is 1920 x 1080 pixels
>> per frame, which is 2.1 Mbyte.
>
> With no compression or chroma subsampling there are 3 bytes per pixel.

Oops, you're right.  However 8 bits per color per pixel is highly optimistic
color resolution.  The actual uncompressed information is probably somewhere
closer to 12 bits/pixel, but I don't have any solid evidence to support
that.


********************************************************************
Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
(978) 742-9014.  Gold level PIC consultants since 2000.

'[TECH] Helmholtz coil manufacturers'
2008\08\05@133042 by Jonathan Hallameyer

picon face
The second manufacturer there is one that Ive already emailed for more
information, and the first manufacturer site looks like it hasnt been
updated in a while, but I'll try to contact them.

On Tue, Aug 5, 2008 at 12:59 PM, M. Adam Davis <stienmanRemoveMEspamgmail.com> wrote:
{Quote hidden}

>> --

'[TECH] Canon HF100 camcorder (was: [EE] SDHC Cards'
2008\08\05@140810 by M. Adam Davis

face picon face
On 8/5/08, Olin Lathrop <spam_OUTolin_piclistRemoveMEspamEraseMEembedinc.com> wrote:
> Spehro Pefhany wrote:
> >> HD video is 1920 x 1080 pixels
> >> per frame, which is 2.1 Mbyte.
> >
> > With no compression or chroma subsampling there are 3 bytes per pixel.
>
> Oops, you're right.  However 8 bits per color per pixel is highly optimistic
> color resolution.  The actual uncompressed information is probably somewhere
> closer to 12 bits/pixel, but I don't have any solid evidence to support
> that.

That would suprise me greatly - I would expect experts to complain
long and loudly if the camcorder only recorded 4096 colors - that
should be readily detectable by eye.

However, I can't seem to find any specific mention of color
information on the canon website or the manual.  I would be surprised
if the Digic II processor reads anything less than 24 bits per pixel
off the CCD, but perhaps someone can take apart the mp4 encoded stream
and tell us what the encoded color space really looks like.

-Adam

--
EARTH DAY 2008
Tuesday April 22
Save Money * Save Oil * Save Lives * Save the Planet
http://www.driveslowly.org

'[TECH] Helmholtz coil manufacturers'
2008\08\05@143724 by M. Adam Davis

face picon face
Well, here are three more manufacturers (the third and fourth show
single axis as cots equipment, but you might be able to work with them
on a triaxial version, or they should be able to direct you to someone
who can do it for you):

www.ets-lindgren.com/page/?i=HelmholtzCoils
http://oersted.com/helmholtz_coils_1.shtml
www.gmw.com/electromagnets/Electromagnet_index.html
http://www.maginst.com/specifications/helmholtz_coils.htm

This person seems to have some experience building and characterizing them:
http://www.chwala.de/hh3eng.html

Depending on your specific needs you might try using a consultant.

This company seems to have some experience in building and
characterizing them as well:
http://www.magnetometer.com/helm.php
though no COTS versions.

Other links of note:
http://www.directindustry.com/prod/stl-systemtechnik/portable-helmholtz-coil-system-28144-99889.html

Interestingly,
http://oersted.com/magnetic_viewing_film.shtml
has magnetic viewing film that looks to be cheap enough for fun and
experimentation... ( -you faintly hear sounds of Adam tucking that
link away for future use- )

Out of curiosity, what's the application?  Why don't you build one
yourself and use a fluxmeter to calibrate it?  A NASA article (
http://www.nasa.gov/offices/oce/llis/0671.html ) gives enough details
on a particular design that you could readily replicate their results
as a starting point.

You could even use a (relatively) cheap three axis magnetometer to add
closed loop feedback to a control system for the coil.
http://www.sparkfun.com/commerce/product_info.php?products_id=244

-Adam

On 8/5/08, Jonathan Hallameyer <TakeThisOuTjmhtauRemoveMEspam@spam@gmail.com> wrote:
{Quote hidden}

'[TECH] Magnetic field viewing film - bistable, hig'
2008\08\05@144715 by M. Adam Davis

face picon face
I thought a lot of you would get a kick out of this:

http://oersted.com/magnetic_viewing_film.shtml

Magnetic field viewing film - green plastic turns black where a field
penetrates the sheet.  High resolution, bi-stable - you reset it by
swiping a magnet across the surface.

Relatively inexpensive - 1 square foot is $40.  A 3"x3" patch is
$4.50.  I could see using this as poor man's e-paper - perhaps making
a high resolution line solenoid array, drawing the 'paper' through,
and using it until it needs new information.  Different from the
magna-doodle ( http://www.howstuffworks.com/magna-doodle.htm ) but
similar in several interesting ways.

-Adam

--
EARTH DAY 2008
Tuesday April 22
Save Money * Save Oil * Save Lives * Save the Planet
http://www.driveslowly.org

'[TECH] Canon HF100 camcorder (was: [EE] SDHC Cards'
2008\08\05@144802 by Spehro Pefhany

picon face
Quoting "M. Adam Davis" <stienmanspam_OUTspam@spam@gmail.com>:

{Quote hidden}

Human vision is significantly less sensitive to chroma (color) detail than
to luminance (brightness) detail. This is taken advantage of in analog  
television signals,first developed in the 1950s, where the chroma  
bandwidth is but a fraction of the luminance bandwidth, and in digital  
video where the chroma signal is sampled at something like 1/4 of the  
resolution of the luminance information. But that's a form of (lossy)  
compression.

What actually happens at the sensor is another kettle of fish again:
http://en.wikipedia.org/wiki/Bayer_filter

Best regards,
Spehro Pefhany
--
"it's the network..."                          "The Journey is the reward"
s...KILLspamspamEraseMEinterlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com


'[TECH] Magnetic field viewing film - bistable, hig'
2008\08\05@150732 by piclist

flavicon
face
On Tue, 5 Aug 2008, M. Adam Davis wrote:
> I thought a lot of you would get a kick out of this:
>
> http://oersted.com/magnetic_viewing_film.shtml
>
> Relatively inexpensive - 1 square foot is $40.  A 3"x3" patch is
> $4.50.  I could see using this as poor man's e-paper - perhaps making
> a high resolution line solenoid array, drawing the 'paper' through,
> and using it until it needs new information.

It would be tricky.  The stuff only really tracks changes between a field
pointed at the paper, and a field paralell to it.  YOu can see this in a
photo from my site...

http://www.ian.org/Magnetics/SeventyTwo14INSqB.jpg

The magnets are set up in an alternating north-south pattern, but you can
see that the squares all look the same as the paper does not show the
difference between north and south magnetic fields.

I think the biggest difficulty would be generating an intense, but very
localized field, or else you erase the pattern you had drawn as you move
down to draw the next line.

But it's cool stuff!

--
Ian Smith
http://www.ian.org

'[TECH] Canon HF100 camcorder (was: [EE] SDHC Cards'
2008\08\05@153639 by olin piclist

face picon face
M. Adam Davis wrote:
> That would suprise me greatly - I would expect experts to complain
> long and loudly if the camcorder only recorded 4096 colors - that
> should be readily detectable by eye.

You can see well more than 4096 colors in a static image.  However when each
pixel is refreshed at least 30 times per second, 12 bits with some temporal
dithering can look very good.

Look at all the color compaction that normal NTSC video gets away with.  The
bandwidth of the color components are greatly reduced from the full
theoretical "pixel" rate.  This color information reduction is based on
human eye perception, so it will work just as well on HD video.  NTSC
composite video looks fine with 8 bits/pixel.

I was giving HD the benefit of the doubt and understanding that it isn't
really compacted into compsite form.  I think even a naive 4-5-3 bit RGB
encoding with +-1/2 LSB of random noise added to each channel before
digitization will look quite good displayed on a normal HD monitor.

I don't know how this particular camera encodes the video, but I was talking
about effective color resolution per individual pixel that you eventually
get to see on a monitor.  Individual frames probably have noticeable noise
on them, but that gets averaged out over a number of frames by the eye,
effectively restoring signal to noise ratio by temporal low pass filtering.


********************************************************************
Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
(978) 742-9014.  Gold level PIC consultants since 2000.

'[TECH]:: Countdown to the Perseid Meteor Shower'
2008\08\05@185428 by Apptech

face
flavicon
face
>From Space Weather:


Space Weather News for August 5, 2008
http://spaceweather.com

COUNTDOWN TO THE PERSEIDS: The annual Perseid meteor shower
peaks one week from today, on Tuesday, August 12th. The best
time to look is during the dark hours before dawn on Tuesday
morning when forecasters expect 50 to 100 meteors per hour.
Get away from city lights if you can; plan a camping trip!
The darker the sky, the more meteors you will see.

The source of the Perseids is Comet Swift-Tuttle, which has
littered the August portion of Earth's orbit with space
dust.  The dusty zone is broad and Earth is already in its
outskirts.  As a result, even before the peak on August
12th, you may see some "early Perseids" streaking across the
night sky. Photos of these early arrivals will be featured
in the days ahead on http://Spaceweather.com as part of our
full coverage of the Perseid meteor shower.

BONUS:  Last Friday's total solar eclipse is history, but
new pictures continue to appear in our photo gallery.  Start
browsing at this URL:
http://spaceweather.com/eclipses/gallery_01aug08_page3.htm


'[TECH] Canon HF100 camcorder (was: [EE] SDHC Cards'
2008\08\05@195115 by Herbert Graf

flavicon
face
On Tue, 2008-08-05 at 12:56 -0400, Spehro Pefhany wrote:
> Quoting Olin Lathrop <EraseMEolin_piclist@spam@spam@spam@embedinc.com>:
>
> > Apptech wrote:
> >> 17 Mb/s x 1/8 Bytes x 7200 seconds / 16 MB ~= 956:1*
> >
> > You slipped a few decimal points.  HD video is 1920 x 1080 pixels per frame,
> > which is 2.1 Mbyte.
>
> With no compression or chroma subsampling there are 3 bytes per pixel.

I really depends on the camera in question.

For completely raw numbers:

For 1080i/720p the pixel rate is 74.25MHz.
For 1080p the pixel rate is 148.5MHz.

Note that these rates include the blanking and sync regions of the video
stream.

The number of bits per pixel varies though. 8bit/colour (24bits/pixel)
used to be the only game in town, 10bits/colour (30bits/pixel) is now
getting common, and 12bits/colour (36bits/pixel) is starting to appear.

For compression it depends on what codec is used, and what the
compression settings are. For true HD content 17Mbps is about the middle
ground (for Bluray the max video bit rate is 40Mbps).

TTYL

'[TECH] Magnetic field viewing film - bistable, hig'
2008\08\05@210540 by Cedric Chang

flavicon
face
> http://oersted.com/magnetic_viewing_film.shtml
>
> Relatively inexpensive - 1 square foot is $40.  A 3"x3" patch is
> $4.50.  I could see using this as poor man's e-paper - perhaps making
> a high resolution line solenoid array, drawing the 'paper' through,
> and using it until it needs new information.


Once you have "written" to this film, how long does the image last ?
How sensitive is it to temperature ?  1)  as far as retaining the  
image   2) as far as writing the image ?
How much light does the film pass through it ?  Could you project an  
image with an overhead projector ?

cc

'[TECH] Helmholtz coil manufacturers'
2008\08\06@025440 by Forrest W. Christian

flavicon
face
Are you trying to build a time machine?

Sorry, that was my first impression (meaning a "Helmholtz coil" sounds
like the type of weird concoction which would be part of a time machine
- you know right alongside the flux capacitor), and after looking at the
pictures of the gear and reading the datasheet at
http://www.meda.com/Data_Sheets/hcs01.pdf , I'm not 100% convinced that
a Helmholtz coil isn't the key component in either a time machine or
other similar devices.

After all, anything which includes the following description:
-----------
"In the open loop system, fixed currents are passed through the coils to
produce a coarse null in the control volume. The null is trimmed to its
final value under computer control. Precision control currents are added
to the fixed currents to generate accurate and stable uniform fields
within the control volume"
-----------
*has* to be from some science-fiction story.  Especially when the
features include "Three Square Concentric Orthogonal Helmholtz Coils"
and "±200,000 nT Control Field Range."

So on a more serious note, what exactly do you use a Helmholtz coil
for?  In the real world, that is...all of the purposes I could come up
with seem rather esoteric or more easily obtained in another way.

-forrest


Jonathan Hallameyer wrote:
{Quote hidden}

'[TECH] Magnetic field viewing film - bistable, hig'
2008\08\06@042302 by Alan B. Pearce

face picon face
>It would be tricky.  The stuff only really tracks changes between a
>field pointed at the paper, and a field paralell to it.  YOu can see
>this in a photo from my site...

Can one still get spray on mag tape developer? I remember we used to get it
from Burroughs, but I think they were marketing someone elses product under
their own name. That was great stuff to use for looking at magnetic fields.

2008\08\06@095636 by M. Adam Davis

face picon face
On 8/6/08, Alan B. Pearce <@spam@A.B.PearcespamspamKILLspamrl.ac.uk> wrote:
> >It would be tricky.  The stuff only really tracks changes between a
> >field pointed at the paper, and a field paralell to it.  YOu can see
> >this in a photo from my site...
>
> Can one still get spray on mag tape developer? I remember we used to get it
> from Burroughs, but I think they were marketing someone elses product under
> their own name. That was great stuff to use for looking at magnetic fields.

Wow, I didn't even know this stuff existed!

http://www.q-card.com/pdf/Developer%20sales%20sheet%20rev2.pdf

Yes, you still can.

-Adam

--
EARTH DAY 2008
Tuesday April 22
Save Money * Save Oil * Save Lives * Save the Planet
http://www.driveslowly.org

2008\08\06@104608 by Alan B. Pearce

face picon face
>Wow, I didn't even know this stuff existed!
>
> http://www.q-card.com/pdf/Developer%20sales%20sheet%20rev2.pdf
>
>Yes, you still can.

Great. Yes it is great fun to use. I did have reason to use it in serious
manner on a couple of occasions, and recommend its use on another couple.

Great for looking at sectoring on disks or (as illustrated on above link)
channels on tape.

'[TECH] Helmholtz coil manufacturers'
2008\08\06@171349 by Sean Breheny

face picon face
I had to look it up but it looks like it is simply an arrangement of
coils used to generate a very uniform magnetic field in a volume -
probably for science experiments and possibly medical instrumentation.

http://en.wikipedia.org/wiki/Helmholtz_Coils

Sean


On Wed, Aug 6, 2008 at 2:56 AM, Forrest W. Christian <spamBeGoneforrestcRemoveMEspamEraseMEimach.com> wrote:
{Quote hidden}

>

'[TECH]:: NASA Phoenix Mars lander 360 degree panor'
2008\08\06@192848 by Apptech

face
flavicon
face
NASA says ...

   " Phoenix Looks Around
Combining more than 400 images, NASA's Phoenix Mars Lander
views its surroundings in the Red Planet's northernmost
region.

The full-circle panorama in approximately true color shows
the polygonal patterning of ground at the landing area,
similar to patterns in permafrost areas on Earth. South is
toward the top. Trenches, where Phoenix's robotic arm has
been exposing subsurface material, are visible in the lower
half of the image. The spacecraft's meteorology mast, topped
by the telltale wind gauge, extends into the sky portion of
the panorama.

Image Credit: NASA/JPL-Caltech/University of Arizona/Texas
A&M University

"

Even the 946 x 710 smaller image is worth seeing

435 kB photo and text

       http://www.nasa.gov/multimedia/imagegallery/image_feature_1145.html

Full size image (8MB, 27 MP)

           http://www.nasa.gov/images/content/265532main_image_1145.jpg

_____________



Apparently, Spring hasn't arrived yet.

:-)



       Russell



'[TECH] Helmholtz coil manufacturers'
2008\08\06@201038 by Forrest Christian

flavicon
face
That's pretty much what I got from it...  I was just wondering if there
was some non-obvious but useful application not in the realm of
scientific experiments as about the only thing I could figure out was
basically what you came up with - some esoteric science experiments and
perhaps testing certain sensors such as electronic compasses and the
like - although it would seem that most apps I can think of would not
require such a complicated device.

That doesn't change the fact that I love the fact that that when you
read the advertising slicks for real versions of this, they sound like
something which some science fiction writer would have just made up.

-forrest

Sean Breheny wrote:
{Quote hidden}

>> -

2008\08\06@203316 by M. Adam Davis

face picon face
Nasa has used them to remove magnetic fields from objects (ie, a
residual field on a piece of hardware going into space).  You don't
want to go to the red planet and worry about ferrite gunking up your
mechanics or sensors.

You can use the coil to cancel out the Earth's magnetic field, and
then test CRT tubes inside it.

You can test sensitive electronic equipment in a strong varying field
before deploying it to a factory where it'll reside next to a monster
motor winding.

You can construct plasma balls inside it and know they aren't going to
zip around due to external fields (or make them move according to your
needs).

You can place atmoic clocks in them to make sure external fields are
compensated for and don't affect the accuracy of the clock.

You can use it with a very sensistive field detector in a closed loop
to enhance the sensitivity or range of the sensor.

-Adam

On Wed, Aug 6, 2008 at 8:10 PM, Forrest Christian <TakeThisOuTforrestcspamimach.com> wrote:
{Quote hidden}

>>> --

'[TECH] Canon HF100 camcorder (was: [EE] SDHC Cards'
2008\08\07@060145 by Peter

picon face
The number of pixels in the camera is almost irrelevant if the signal is
recorded or transmitted. Current standards are mostly based on D2 which uses
color decimation and optional (simple?) compression. Current schemes compress
like 4:2:2 (for bits of Y, B-Y and G-Y respectively). This is the case for most
satellite tv and broadcast feed data. 8:8:8 is never used afaik. The internal
data paths in current state of the art ENG and pro consumer cameras ($3k to $30k
range) are 3 x 12 or 14 bits at the full pixel rate (can be >20MHz for HDTV),
one channel per trichrome imager. Single pickup cameras don't count
quality-wise. That fire-hose is compressed to D2 or to internal studio bus
bandwidths before leaving the camera head. Most current HDTV and MPEG/OGG etc
standards are designed around the constraints imposed by such data streams,
adapted to 'reasonable' screen refresh rates and screen sizes. For example
decompressed MPEG2 encoded data bears a suspicious resemblance to certain D2
data formats (not by accident).

Peter


'[TECH]:: The sun is going out'
2008\08\07@132916 by Apptech

face
flavicon
face
NASA plot of sunspot activity.
Updated monthly.

       http://www.swpc.noaa.gov/SolarCycle/index.html

I've been saving these each month for some months now and
it's been interesting to see the activity continue to drop
towards zero while the predictions gamely urge it to
splutter into life.

Maunder minimum in the wings, or just a hiccup. Stay tuned,
could be interesting.


       Russell

2008\08\07@133655 by PAUL James

picon face

All,

As I'm sure you know, the sunspot cycle has a frequency of about 11
years.
So if we are in the middle of this period, sunspot activity will be at a
mininum.  
In another few years, you'll see it going back up again.
Check out the ARRL website for more info.
       

                                                       Regards,

                                                         Jim


{Original Message removed}

2008\08\07@133910 by Chris Smolinski

flavicon
face
>NASA plot of sunspot activity.
>Updated monthly.
>
>         http://www.swpc.noaa.gov/SolarCycle/index.html
>
>I've been saving these each month for some months now and
>it's been interesting to see the activity continue to drop
>towards zero while the predictions gamely urge it to
>splutter into life.
>
>Maunder minimum in the wings, or just a hiccup. Stay tuned,
>could be interesting.

Some are suggesting a double minimum, as has occurred before. IMHO
it's tough to predict how the Sun should behave, we only have two
dozen solar cycles worth of data to work with - a few centuries out
of the 5 billion year age of the Sun.

NASA/etc have been very public in saying that the Sun is acting
normally, everything is fine, nothing to see here folks, move along.
Most likely to calm fears that we are headed into a Maunder or Dalton
minimum.  I also would not be surprised if  some of it is to counter
statements that the reduced solar activity is coinciding with a drop
in global temperatures, which might lead some to suspect that man
made global warming is not all it is claimed to be, which could have
a negative impact on government climate research funding ;-)

FWIW, a 2006 forecast from a new solar model is doing pretty well right now:
http://www.arrl.org/w1aw/prop/2006-arlp010.html


--

---
Chris Smolinski
Black Cat Systems
http://www.blackcatsystems.com

2008\08\07@134120 by M. Adam Davis

face picon face
How long back do we have usable records of solar spot activity?  Even
though the human lifespan is short, the solar lifespan is long and I
would be surprised if any signal in the frequency range of a human
lifespan is anything more than noise...

-Adam

On 8/7/08, Apptech <EraseMEapptech.....spamKILLspamparadise.net.nz> wrote:
{Quote hidden}

> -

'[TECH] Beagle Board'
2008\08\07@154034 by Alex Harford

face picon face
Just saw this on the Digikey front page:
http://beagleboard.org/

600MHz ARM

Able to do 720p decoding with the DSP + mplayer patches

It seems like it's a very community oriented website, on their
hardware accessories page, they list Digikey and Sparkfun as possible
vendors.  But they also allow people to tag pages through the
del.icio.us website: delicious.com/tag/beagleboard+peripheral

2008\08\07@173533 by Peter Loron

flavicon
face
Yeah, saw that too. Looks very slick, although I'm mystified as to why  
they put so much effort into providing good multimedia capabilities  
and failed to put an ethernet interface on there.

It could make a great SOHO Asterisk box if you stored voicemail on a  
network mounted volume.

-Pete

On Aug 7, 2008, at 12:40 PM, Alex Harford wrote:

{Quote hidden}

> --

2008\08\07@182019 by M. Adam Davis

face picon face
Well, they built out most of the functions of the OMAP processor, and
the processor doesn't include an ethernet MAC.

I imagine they also wanted to avoid adding cost (or increasing board
size) where it might not be used, since the USB is high speed
(480mbps) and already supports ethernet, wifi, and bluetooth modules
out of the box.

Still, I know one of the reasons so many linux boards have ethernet
onboard is that it's the fastest way to upload linux and a disk image
- right now the board doesn't support USB bootloading, so you're stuck
with serial (ugh!), JTAG (still not very fast), or using a memory card
(They brought back the venerable sneakernet!).

Once past bootstrapping your device, though, using a USB ethernet or
wireless adaptor doesn't seem so bad, and gives you a little bit of
flexibility.

-Adam

On 8/7/08, Peter Loron <spampeterlspamstandingwave.org> wrote:
{Quote hidden}

2008\08\07@183011 by Mark Rages

face picon face
On Thu, Aug 7, 2008 at 5:20 PM, M. Adam Davis <stienmanSTOPspamspamgmail.com> wrote:
> Once past bootstrapping your device, though, using a USB ethernet or
> wireless adaptor doesn't seem so bad, and gives you a little bit of
> flexibility.
>

According to the manual, the USB host port has been removed because it
didn't work right.

I guess you could use TCP over a Linux "gadget" USB device connection.
It's only moderately painful.

Regards,
Mark
markrages@gmail
--
Mark Rages, Engineer
Midwest Telecine LLC
markragesSTOPspamspamKILLspammidwesttelecine.com

2008\08\07@191658 by M. Adam Davis

face picon face
There were two USB ports, one host only, and one high speed on the go.
You can still connect USB hubs and devices to the OTG USB port in
host mode, and the wiki seems to indicate that several ethernet and
wireless adaptors work with the current linux builds.

-Adam

On 8/7/08, Mark Rages <@spam@markrages.....spamspamgmail.com> wrote:
{Quote hidden}

> -

'[TECH]:: The sun is going out'
2008\08\08@040737 by Alan B. Pearce

face picon face
>As I'm sure you know, the sunspot cycle has a frequency of
>about 11 years.

Something I saw recently gave it as varying between 8 and 14 years. I hadn't
appreciated the variation was that wide until I saw the article, I had
always taken it as being a solid 11 years.

'[TECH] Beagle Board'
2008\08\08@040749 by Peter Loron

flavicon
face
Yeah, it just seems so clunky to have to add a dongle, and have the OS  
overhead of another protocol stack in he way.

-Pete

On Aug 7, 2008, at 4:16 PM, M. Adam Davis wrote:

{Quote hidden}

>> --

'[TECH]:: The sun is going out'
2008\08\08@081912 by Apptech

face
flavicon
face
> >As I'm sure you know, the sunspot cycle has a frequency
> >of
>>about 11 years.

> Something I saw recently gave it as varying between 8 and
> 14 years. I hadn't
> appreciated the variation was that wide until I saw the
> article, I had
> always taken it as being a solid 11 years.

Current cycle is 'very anomalous' and causing much concern.
It MAY pull out but at present the new cycle is far far far
overdue by any usual standards *. The prediction setters at
NASA and all are hanging tough and did not update the
predictions this year that they had made last year. It is
presently creeping outside their lower limits with every
sign of continuing BUT could change at any moment. The next
few months will show if the trend continues but interesting
times may be ahead.

Note that this all doesn't address the validity or otherwise
of the 'science'  behind global warming. We could go through
eg a 15 year very low temperature blip (eg a Maunder
minimum) - or longer, and the manmade variations, whatever
they are, could be swamped, without changing the basic idea
either way. Worst case we may hope that the CO2 scenarios
are true as we may want to burn as much carbon as we can a
few decades on :-(.

* As we are also long long overdue for the next ice age
(about 2000 years!) then one can hope that what we are
seeing now is not the first stages of it all starting to get
REALLY cold. As an idea, much of North American continent
can see about 1000-2000 feet of ice cover in an ice age.
Makes clearing the walks very difficult.



       Russell

>NASA plot of sunspot activity.
>Updated monthly.
>
>         http://www.swpc.noaa.gov/SolarCycle/index.html
>


2008\08\08@092447 by PAUL James

picon face

Alan,

This is true.  However, the median value is still 11 years.  In other
words, if you look between two like magnitudes on the sunspot time line,
it could be anywhere between 8 years and 14 years.  If you average the
magnitudes over the timeline, they will average to about 11 years.  Or
11 years plus or minus 3.   Anyway, 11 years is just a reference point.
It isn't carved in stone as you've pointed out.

       
       
Regards,

       
Jim

                                                                       



{Original Message removed}

'[TECH]:: NASA to Realign Constellation Program Mil'
2008\08\11@211817 by Apptech

face
flavicon
face
August 11th.

WASHINGTON -- In a news conference Monday, NASA managers
discussed how the agency will be adjusting the budget,
schedule and technical performance milestones for its
Constellation Program to ensure the first crewed flight of
the Ares I rocket and Orion crew capsule in March 2015.

       http://www.nasa.gov/home/hqnews/2008/aug/HQ_08-205_Constellation_realignment.html

Constellation home page:

       http://www.nasa.gov/mission_pages/constellation/main/index.html



       R



'[TECH] Canon HF100 camcorder (was: [EE] SDHC Cards'
2008\08\11@212322 by M. Adam Davis

face picon face
On Mon, Aug 4, 2008 at 11:34 PM, M. Adam Davis <spam_OUTstienmanTakeThisOuTspamEraseMEgmail.com> wrote:
> The software included is, for all intents and purposes,
> useless

Wow I'm long winded.

Ok, I actually read the manual for the software that came with it
(wait, RTFM works?) and it DOES do simple conversions to standard
definition video, and video suitable for online players (such as
youtube).  I haven't tried its editing features, but it's supposed to
be able to basic editing operations (clipping, sequencing, etc).
Further, it will write to DVDs, and I believe blue ray if you have a
burner.  It will also write AVCHD files to DVD which, I'm told, some
blue ray players play natively.

However, I still ended up getting Ulead video studio, as I wanted to
also convert my video to high definition mpeg2 content, which the
included program did not do, and of course Ulead does so much more
with editing and creation of DVDs (menus, etc), blue ray (and HDDVD if
you bought into that), and will convert directly to a variety of
formats easily and quickly - such as iPod, Zune, etc.  At $99 it was
worth it.  It also converts faster - it appears to be 4 times realtime
for the few different types of conversions I did (high resolution
AVCHD to high resolution mpeg2, high resolution AVCHD to 720p mpeg2,
high resolution to youtube (320x240 15fps)) - this is on a mid range
machine (Core 2 duo 6600, 2.4GHz, 2GB RAM, and the lowest video card
that was still compatible with Vista).  It uses both cores pretty
well.  So the 75 second clip I'll be linking to later took 300 seconds
to convert into the higher resolution formats, and if I remember
correctly the conversion to youtube quality was much closer to
realtime.

Unfortunately I've already suffered a hardware failure - the automatic
shutter on the front no longer opens and closes.  It's lightly held by
springs, so I can hold it open, and it doesn't appear to have an error
for closed shutter (ie, some camcorders will not record when this
happens, even if you hold the shutter open).  So I'm going to fashion
a little clip to hold it open to record a meeting tomorrow, and then
send it off to Canon.  They were pleasant to deal with, and it sounds
like including shipping time I can expect to be out of commission for
2-3 weeks.  Not ideal, but we'll see how it goes.

Lastly, I'm lazy but I _did_ promise samples, which I hope to link to
tonight or tomorrow.

-Adam

--
EARTH DAY 2008
Tuesday April 22
Save Money * Save Oil * Save Lives * Save the Planet
http://www.driveslowly.org

2008\08\12@080554 by olin piclist

face picon face
M. Adam Davis wrote:
> At $99 it was worth it.

Good thing you feel that way because you paid $20 more than it costs right
on its own web site.


********************************************************************
Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
(978) 742-9014.  Gold level PIC consultants since 2000.

2008\08\12@083727 by M. Adam Davis

face picon face
I did get that discount, sorry for the mistake - first time customers
get $20 off, so at $79 it is an ever better deal.

Thanks for the correction!

-Adam

On 8/12/08, Olin Lathrop <EraseMEolin_piclistspamBeGonespamKILLspamembedinc.com> wrote:
> M. Adam Davis wrote:
> > At $99 it was worth it.
>
> Good thing you feel that way because you paid $20 more than it costs right
> on its own web site.
>
>
> ********************************************************************
> Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
> (978) 742-9014.  Gold level PIC consultants since 2000.
> -

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