Searching \ for 'headlight' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: www.piclist.com/techref/index.htm?key=headlight
Search entire site for: 'headlight'.

No exact or substring matches. trying for part
PICList Thread
'Vehicle Automatic headlight controller'
2000\02\17@181655 by Terry

flavicon
face
While i'm at it, here's another freebie.

Normal dawn/dusk automotive headlight sensors simply detect light levels
for safe driving conditions and turn the headlights on or off automatically.

Where i'm at, we have 2 tunnels with "fail safe" lighting. This would cause
the dawn/dusk controller to mistake the artificial lighting as safe
lighting condition and turn the headlights off.

Murphy's law takes over and the fail safe lighting fails. Most drivers
don't bother to turn their headlights on even tho they're supposed to while
travelling through the tunnels. One heck of a pile up ensues.

Solution, make everybody turn their headlights on all the time or have a
light sensor connected to a PIC. As far as road/tunnel lightings are
concerned, everything is run off AC power. Even the dimming ballast is sort
of AC at 20kHz. So artificial lighting "blinks" anywhere from 50Hz to 40kHz
(to be on the safe side).

Additional functions programmed into the PIC would be:

Presettable time delay headlight shutter-offer.
Battery voltage monitor.
Auto headlight shutter-offer when battery's low (for old cars without
headlight warning or when you're parked and making 6 foot shadow animals to
entertain your kids)
Blown bulb indicator


Cheers
Terry

..... another one joins the Titanic

2000\02\17@192154 by Wagner Lipnharski

flavicon
face
Oh come on, it is quite simple.
Once the car's ignition is on, if the light sensor sees dark it turns
the car lights on immediately and stay on until you turn ignition off,
or if the sensor sees light for more than 10 minutes...  by the way, I
believe that the law says your car MUST stay with headlights on all the
time from dusk to dawn, doesn't matter what.

Terry wrote:
{Quote hidden}

2000\02\18@133351 by Terry

flavicon
face
Ahh.. so it turns your headlights on in a dimly lit carpark or garage and
remains on for 10 mins after you hit the summer noon day sun then keeps
your headlights off while you're travelling through an artificially
illuminated tunnel?

So what's the big deal if the tunnel is brightly lit? Ever been trapped in
a pitch black elevator? Or drive at 100km/h blindfolded?




At 07:20 PM 2/17/00 -0500, you wrote:
>Oh come on, it is quite simple.
>Once the car's ignition is on, if the light sensor sees dark it turns
>the car lights on immediately and stay on until you turn ignition off,
>or if the sensor sees light for more than 10 minutes...  by the way, I
>believe that the law says your car MUST stay with headlights on all the
>time from dusk to dawn, doesn't matter what.


'[EE]: Modulating a headlight'
2001\06\28@191429 by Miles McKinnon
picon face
I am building a motorcycle headlight modulator using a PIC to monitor
ambient light and a few other things.  Anyway, the PIC has to modulate the
headlight ( ~ 4Amps) at a arount 240Hz or so.

There are a few legal stipulations.  They say that you cannot switch the
ground, you must switch the +12V to the headlight.  I want to use a low Rds
HEXFET or simular transistor, but I think I would need a P-Channel device.

Is a P-Channel Mosfet difficult to drive from a TTL logic level, such as a
PIC.

Thanks for any help.

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2001\06\28@200059 by Dan Michaels

flavicon
face
Miles McKinnon wrote:
>I am building a motorcycle headlight modulator using a PIC to monitor
>ambient light and a few other things.  Anyway, the PIC has to modulate the
>headlight ( ~ 4Amps) at a arount 240Hz or so.
>

Miles, 240 hz is a little high, if your intent is to have
people see the flicker as a warning signal. The flicker
fusion frequency of humans is about 20 hz, so even 24 hz
may be too high. Might be good for insects however.

I think somewhere around 4 hz is the most noticeable to
humans. You might do a web search on "psychophysics".

good luck,
- dan michaels
http://www.oricomtech.com
========================

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2001\06\28@201540 by Nicholas Irias

flavicon
face
If you cant find a low Rds P-channel FET, check out the high side FET
drivers at micrel.com.  They have built in charge pumps to switch an
N-channel FET at the appropriate voltage for high side switching.

I think headlight modulating on cycles is 3 or 4 times a second.  Maybe you
meant to say 240 times per minute rather than 240 Hz?


{Original Message removed}

2001\06\28@203251 by Miles McKinnon

picon face
Yes, your right.  I meant to say 240 times per minute, which is 4 Hz.





----- Original Message -----
From: "Nicholas Irias" <spam_OUTniriasTakeThisOuTspamPACBELL.NET>
To: <.....PICLISTKILLspamspam@spam@MITVMA.MIT.EDU>
Sent: Thursday, June 28, 2001 5:07 PM
Subject: Re: [EE] Modulating a headlight


> If you cant find a low Rds P-channel FET, check out the high side FET
> drivers at micrel.com.  They have built in charge pumps to switch an
> N-channel FET at the appropriate voltage for high side switching.
>
> I think headlight modulating on cycles is 3 or 4 times a second.  Maybe
you
{Quote hidden}

the
> > headlight ( ~ 4Amps) at a arount 240Hz or so.
> >
> > There are a few legal stipulations.  They say that you cannot switch the
> > ground, you must switch the +12V to the headlight.  I want to use a low
> Rds
> > HEXFET or simular transistor, but I think I would need a P-Channel
device.
{Quote hidden}

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2001\06\28@204318 by Robert A. LaBudde

flavicon
face
At 08:00 PM 6/28/01 -0400, Dan wrote:
>Miles McKinnon wrote:
> >I am building a motorcycle headlight modulator using a PIC to monitor
> >ambient light and a few other things.  Anyway, the PIC has to modulate the
> >headlight ( ~ 4Amps) at a arount 240Hz or so.
> >
>
>Miles, 240 hz is a little high, if your intent is to have
>people see the flicker as a warning signal. The flicker
>fusion frequency of humans is about 20 hz, so even 24 hz
>may be too high. Might be good for insects however.
>
>I think somewhere around 4 hz is the most noticeable to
>humans. You might do a web search on "psychophysics".

Check it out on yourself, first!

This frequency can induce epilectic seizures. It's also commonly used in
inducing hypnosis. Neither of these bode well for the motorcycle driver.

================================================================
Robert A. LaBudde, PhD, PAS, Dpl. ACAFS  e-mail: EraseMEralspam_OUTspamTakeThisOuTlcfltd.com
Least Cost Formulations, Ltd.            URL: http://lcfltd.com/
824 Timberlake Drive                     Tel: 757-467-0954
Virginia Beach, VA 23464-3239            Fax: 757-467-2947

"Vere scire est per causas scire"
================================================================

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2001\06\28@205420 by Miles McKinnon

picon face
240 cycles (+-40) per minute is the recommended rate:

See:
http://www.tc.gc.ca/securiteroutiere/mvstm_tsd/tsd/1080-m.htm#_Toc%20S5.6


That is a link to the Canadian law for motorcycle headlight modulators.
American law is the same.

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2001\06\28@222114 by jim

flavicon
face
Miles,

If you want a low RDSon, shouldn't you use an N channel device?
And I have had no problems driving a FET if I use a pullup resistor,
(or pulldown if that's what I need).

                                                           Regards,

                                                               Jim
{Original Message removed}

2001\06\29@025406 by Miles McKinnon

picon face
The reason to modulate the headlight is for visability.  If you see
something in your rearview mirror flashing at 240 cycles per minute, it will
stand out.  That makes motorcyclists safer.  This isn't a new idea.

Jim, I could use an N-Channel, but if my load is connected between source
and ground, the gate turn on voltage will be (if it is a logic level FET) ~
12V + 5V.  Without using a charge pump IC, 17V isn't available easily on a
standard automotive application.  That is the reason of a P-Channel.




{Original Message removed}

2001\06\29@055801 by jeethur

flavicon
face
Dan,

I guess you did'nt quite understand Miles' plans.
I guess, he wants to control the brightness of the Headlight with PWM.
And if that is the case  I suggest that Miles can go for an even
higher frequency. May be a couple of Khz. Since as a rule, the Higher
the frequency, the greater the efficency.

Jeethu Rao
http://www.jeethurao.com

{Original Message removed}

2001\06\29@074654 by Bob Ammerman

picon face
> Jim, I could use an N-Channel, but if my load is connected between source
> and ground, the gate turn on voltage will be (if it is a logic level FET)
~
> 12V + 5V.  Without using a charge pump IC, 17V isn't available easily on a
> standard automotive application.  That is the reason of a P-Channel.

That's what your PIC is for. How about a PIC12C508A.

One software oscillator to drive a voltage doubler to get the hi voltage for
the NPN FET.

Another one to blink your headlights.

Maybe even use PWM to softstart the light and reduce stress on the filament?

Bob Ammerman
RAm Systems
(contract development of high performance, high function, low-level
software)

>
>
>
> {Original Message removed}

2001\06\29@090719 by Olin Lathrop

face picon face
> I am building a motorcycle headlight modulator using a PIC to monitor
> ambient light and a few other things.  Anyway, the PIC has to modulate the
> headlight ( ~ 4Amps) at a arount 240Hz or so.
>
> There are a few legal stipulations.  They say that you cannot switch the
> ground, you must switch the +12V to the headlight.  I want to use a low
Rds
> HEXFET or simular transistor, but I think I would need a P-Channel device.
>
> Is a P-Channel Mosfet difficult to drive from a TTL logic level, such as a
> PIC.

You wont be able to drive it with 0-5V when it is sitting at 12V.  However,
it should be rather easy to generate the 0 to 12V gate drive.  Most FETs
will fully switch with 12V gate drive.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olinspamspam_OUTembedinc.com, http://www.embedinc.com

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email @spam@listservKILLspamspammitvma.mit.edu with SET PICList DIGEST in the body


2001\06\29@090728 by Olin Lathrop

face picon face
> And if that is the case  I suggest that Miles can go for an even
> higher frequency. May be a couple of Khz. Since as a rule, the Higher
> the frequency, the greater the efficency.

Lower frequencies are more efficient because the switching elements spend a
higher portion of the time either fully on or fully off.  You can think of
it as a fixed amount of energy lost at each switch transition.  Therefore,
the slower the rate of transitions, the lower the power loss.

The reason for higher PWM frequency is so that the load "sees" the average
on not the individual pulses.  A few 10s of Hz is sufficient for an
incandescent light bulb, a few 100Hz for most motors, but you need close to
100KHz if you are trying to produce high fidelity audio.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, KILLspamolinKILLspamspamembedinc.com, http://www.embedinc.com

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email RemoveMElistservTakeThisOuTspammitvma.mit.edu with SET PICList DIGEST in the body


2001\06\29@092144 by t F. Touchton

flavicon
face
part 1 1674 bytes content-type:text/plain; charset=us-ascii
Back it down to 14hz and you can trip all the Priority Green systems here
in the US... have a green light everywhere you go!!! (and alot of other mad
drivers!!!).  Of course, this is probably illegal.

Scott F. Touchton
1550 Engineering Manager
JDS Uniphase



                   Dan Michaels
                   <oricom@USWEST        To:     spamBeGonePICLISTspamBeGonespamMITVMA.MIT.EDU
                   .NET>                 cc:
                   Sent by: pic          Subject:     Re: [EE]: Modulating a headlight
                   microcontrolle
                   r discussion
                   list
                   <PICLIST@MITVM
                   A.MIT.EDU>


                   06/28/01 08:00
                   PM
                   Please respond
                   to pic
                   microcontrolle
                   r discussion
                   list






Miles McKinnon wrote:
>I am building a motorcycle headlight modulator using a PIC to monitor
>ambient light and a few other things.  Anyway, the PIC has to modulate the
>headlight ( ~ 4Amps) at a arount 240Hz or so.
>

Miles, 240 hz is a little high, if your intent is to have
people see the flicker as a warning signal. The flicker
fusion frequency of humans is about 20 hz, so even 24 hz
may be too high. Might be good for insects however.

I think somewhere around 4 hz is the most noticeable to
humans. You might do a web search on "psychophysics".

good luck,
- dan michaels
http://www.oricomtech.com
========================

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.





part 2 3124 bytes content-type:application/octet-stream; (decode)

part 3 136 bytes
--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email TakeThisOuTlistservEraseMEspamspam_OUTmitvma.mit.edu with SET PICList DIGEST in the body


2001\06\29@110231 by Dan Michaels

flavicon
face
Jeethu Rao wrote:
>Dan,
>
>I guess you did'nt quite understand Miles' plans.
>I guess, he wants to control the brightness of the Headlight with PWM.
>And if that is the case  I suggest that Miles can go for an even
>higher frequency. May be a couple of Khz. Since as a rule, the Higher
>the frequency, the greater the efficency.
>

Jeethu, I think he wants to modulate it at 4 hz [240 cpm],
which is a rate the human eye can perceive. He can either
turn it on and off completely at this rate, which might
shorten the life of the lamp, or modulate a high frequency
PWM at 4 hz, as you suggest, to control intensity.

- dan
================

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email RemoveMElistservspamTakeThisOuTmitvma.mit.edu with SET PICList DIGEST in the body


'[OT]: Priority Green was Modulating a headlight'
2001\06\29@111626 by michael brown

flavicon
face
Scott,

I am very interested in any information you could give me about Priority
Green specs.  Living in Houston is unbelievable.  I swear the oil companies
are in control of the traffic light timing.  I have never been anywhere else
in the US where you had to stop for approx 90% (this is not an exaggeration)
of every traffic light you encounter.  It simply has to be seen to be
believed.  It's so bad that people who are approaching a light that is green
will begin to slow down (preparing to stop), because they have been so well
conditioned.  They seem to think that something is wrong with the light, and
it might be green in both directions.  I admit that after eleven years of
this stuff, I am skeptical of greens too.

But you should see the way that people will race thru a red even though it's
been red for more than three seconds.  It's absolutely astounding.

Not that I would ever do anything illegal, I am still interested in the
specs. ;-D

Michael Brown
Instant Net Solutions
http://www.KillerPCs.net

"In the land of the blind, he who has one eye is king"

{Original Message removed}

2001\06\29@113453 by t F. Touchton

flavicon
face
part 1 3855 bytes content-type:text/plain; charset=us-ascii
You will get a ticket, I know.  My old boss loved the idea, so we built him
a unit based on a strobe tube and used an IR filter to "hide" the flash.
Of course, when we did this, he told us it was a development project for a
product he was going to sell to the fire departments.  Anyway.. the thing
got mounted on the top of his truck... he got away with it for about 2
months.  Then the police caught on.  They staked out the local big
intersection, and discovered that the same Ford pickup (with the big shiny
reflector up on top) was always going through the intersection when the
priority green system activated.  He got fined.

It is a very simple system.  All you need to do is pulse modulate an IR
source at a 14hz rate (flash at 14hz rate).  It is tough to use point
sources (such as LED's) since they must be pointed at the receiver on the
light pole.  We used the strobe to get a broad emission.

Now for the ethics:  This info is in the public domain (so I am sharing
nothing confidential).  There are companies out there who will sell you
this equipment.  You can also sell this equipment to municipalities.  If
you abuse this system you will get in trouble with the authorities.  I do
not condone use of this system.  I have seen very close calls caused by
fire trucks and ambulances (let alone nuts in pickup trucks).  People get
used to the pattern at a traffic light, and when the light suddenly changes
people are caught by surprise.

Scott



                   michael brown
                   <n5qmg@AMSAT.O        To:     PICLISTEraseMEspam.....MITVMA.MIT.EDU
                   RG>                   cc:
                   Sent by: pic          Subject:     [OT]: Priority Green was Modulating a headlight
                   microcontrolle
                   r discussion
                   list
                   <PICLIST@MITVM
                   A.MIT.EDU>


                   06/29/01 10:44
                   AM
                   Please respond
                   to pic
                   microcontrolle
                   r discussion
                   list






Scott,

I am very interested in any information you could give me about Priority
Green specs.  Living in Houston is unbelievable.  I swear the oil companies
are in control of the traffic light timing.  I have never been anywhere
else
in the US where you had to stop for approx 90% (this is not an
exaggeration)
of every traffic light you encounter.  It simply has to be seen to be
believed.  It's so bad that people who are approaching a light that is
green
will begin to slow down (preparing to stop), because they have been so well
conditioned.  They seem to think that something is wrong with the light,
and
it might be green in both directions.  I admit that after eleven years of
this stuff, I am skeptical of greens too.

But you should see the way that people will race thru a red even though
it's
been red for more than three seconds.  It's absolutely astounding.

Not that I would ever do anything illegal, I am still interested in the
specs. ;-D

Michael Brown
Instant Net Solutions
http://www.KillerPCs.net

"In the land of the blind, he who has one eye is king"

{Original Message removed}
part 2 4253 bytes content-type:application/octet-stream; (decode)

part 3 136 bytes
--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email EraseMElistservspammitvma.mit.edu with SET PICList DIGEST in the body


'[EE]: Modulating a headlight'
2001\06\29@113501 by Roman Black

flavicon
face
Yep, I have to throw my reliability 2 cents in here,
if you are gong to modulate a motorbike headlight,
typically a 4 amp to 6 amp 12v filament, you need
to keep it warm in the off periods. And at 4Hz it
will not turn off completely anyway as they take 0.5
sec to cool and "turn off".

My suggestion is to run the thing with some current
in the "off" period, maybe 1.5A, then bump it to the
full 4A for the "on" period. This might simplify the
circuit a bit as the semi device only has to switch
2.5A. Anyone who built a light chaser or other
incandescent bulb flasher knows the failure rate of
the bulbs if you don't keep the filament hot. :o)
-Roman



Dan Michaels wrote:
{Quote hidden}

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email RemoveMElistservEraseMEspamEraseMEmitvma.mit.edu with SET PICList DIGEST in the body


'[OT]: Priority Green was Modulating a headlight'
2001\06\29@113652 by Dan Michaels

flavicon
face
MB wrote:
.....
 Living in Houston is unbelievable.  I swear the oil companies
>are in control of the traffic light timing.  I have never been anywhere else
>in the US where you had to stop for approx 90% (this is not an exaggeration)
>of every traffic light you encounter.

It used to be, in Boulder, if you were the 1st guy at the light,
and peeled off when it turned green, and drove 15 MPH over the
limit, you could just make it through the next light. Unfortunately,
the city caught on to us getting away with this.
============

>
>But you should see the way that people will race thru a red even though it's
>been red for more than three seconds.  It's absolutely astounding.
>

They did a study and found out that, in Boulder, an average of 4 cars
continue through after the light turns red.

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email RemoveMElistservspam_OUTspamKILLspammitvma.mit.edu with SET PICList DIGEST in the body


'[EE]: Modulating a headlight'
2001\06\29@120329 by Dan Michaels

flavicon
face
Roman.B wrote:
.......
Anyone who built a light chaser or other
>incandescent bulb flasher knows the failure rate of
>the bulbs if you don't keep the filament hot. :o)


And, of course, my 100W GE light bulbs always seems to
go pffffft right when I turn on the light switch. I am
sure that GE designs the cold resistance of the filaments
in such as way as to maximize the retirement payoff for
Jack Welch.

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email RemoveMElistservTakeThisOuTspamspammitvma.mit.edu with SET PICList DIGEST in the body


2001\06\29@121139 by Roman Black

flavicon
face
Dan Michaels wrote:
>
> Roman.B wrote:
> .......
>  Anyone who built a light chaser or other
> >incandescent bulb flasher knows the failure rate of
> >the bulbs if you don't keep the filament hot. :o)
>
> And, of course, my 100W GE light bulbs always seems to
> go pffffft right when I turn on the light switch. I am
> sure that GE designs the cold resistance of the filaments
> in such as way as to maximize the retirement payoff for
> Jack Welch.


Hi Dan, yep Jinx had an excellent chart of bulb
life and voltage. I posted some calcs here a while
back showing that in 240vac countries the 60w globes
get 4x or more the startup current than in 110v countries,
and why adding a 5% volts drop resistor gives almost
infinite bulb life.

I have an incubator here, with a 100w bulb as the heater,
and it has survived months of controlled switching a
couple of times per minute to maintain temperature.
I dropped 7% across a resistor before the bulb.
:o)
-Roman

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email EraseMElistservspamspamspamBeGonemitvma.mit.edu with SET PICList DIGEST in the body


'[OT]: Priority Green was Modulating a headlight'
2001\06\29@124348 by James Paul

flavicon
face
Michael,

I've seen it every day for the last 18 years and I still don't
believe it.

                                        Regards,

                                          Jim

On Fri, 29 June 2001, michael brown wrote:

{Quote hidden}

> {Original Message removed}

2001\06\29@130712 by michael brown

flavicon
face
> MB wrote:
> .....
>   Living in Houston is unbelievable.  I swear the oil companies
> >are in control of the traffic light timing.  I have never been anywhere
else
> >in the US where you had to stop for approx 90% (this is not an
exaggeration)
> >of every traffic light you encounter.
>
> It used to be, in Boulder, if you were the 1st guy at the light,
> and peeled off when it turned green, and drove 15 MPH over the
> limit, you could just make it through the next light. Unfortunately,
> the city caught on to us getting away with this.

This sounds like some of the long straight main roads running outside of
downtown.  If you drive 47 in the 35 you will keep just making the lights.
Fortunately 47 in a 35 is nothing unusual around houston.  The defacto
standard here seems to be take the speed limit + 10 and drive that speed
without fear of repercussion.  Nearly everyone does it.  This town is truly
amazing.  Turn signals are not required here, even in front of police when
shoving your way in.  In fact, if you see someone using a turn signal, be
careful.  They seem to be used as "Lookout! I'm fixin' to do something
stupid" indicators.

> ============
>
> >
> >But you should see the way that people will race thru a red even though
it's
> >been red for more than three seconds.  It's absolutely astounding.
> >
>
> They did a study and found out that, in Boulder, an average of 4 cars
> continue through after the light turns red.
Is that all? ;-D

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email RemoveMElistservKILLspamspammitvma.mit.edu with SET PICList DIGEST in the body


'[EE]: Modulating a headlight'
2001\06\29@130921 by Dan Michaels

flavicon
face
Roman wrote:

>> And, of course, my 100W GE light bulbs always seems to
>> go pffffft right when I turn on the light switch. I am
>> sure that GE designs the cold resistance of the filaments
>> in such as way as to maximize the retirement payoff for
>> Jack Welch.
>
>
>Hi Dan, yep Jinx had an excellent chart of bulb
>life and voltage. I posted some calcs here a while
>back showing that in 240vac countries the 60w globes
>get 4x or more the startup current than in 110v countries,
>and why adding a 5% volts drop resistor gives almost
>infinite bulb life.
>

Roman, fantastic, so 5% is all it takes?

And I wonder - are the guys selling bulbs outside the US
mainly subsidiaries of american conglomerates like GE?
This would explain a lot.

- dan

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email listservSTOPspamspamspam_OUTmitvma.mit.edu with SET PICList DIGEST in the body


'[OT]: Priority Green was Modulating a headlight'
2001\06\29@131140 by Jeff DeMaagd

flavicon
face
I am somewhat convinced that traffic engineering is the art of making every
path from point A to point B equally inconvenient.  Of course, it's probably
because the engineers are saddled with insane road commission and other
legal requirements done ostensibly for our own good but just ends up
frustrating everyone.

There's one shop I go to somewhat regularly that is a commercial zone,
surrounded by residential zones, the only way to get there is to drive 5 to
10 miles through 25 MPH areas with a bad mishmash of one way roads, the
roads that have traffic signals have poor light timings and many goofy road
routings, into a six way intersection.

Jeff

----- Original Message -----
From: michael brown <spamBeGonen5qmgSTOPspamspamEraseMEAMSAT.ORG>
[snip]

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email KILLspamlistservspamBeGonespammitvma.mit.edu with SET PICList DIGEST in the body


'[EE]: Modulating a headlight'
2001\06\29@131534 by michael brown

flavicon
face
> And, of course, my 100W GE light bulbs always seems to
> go pffffft right when I turn on the light switch. I am
> sure that GE designs the cold resistance of the filaments
> in such as way as to maximize the retirement payoff for
> Jack Welch
Part of the problem is that the vacuum "leaked out ;-D" the last time you
turned it off and it cooled, breaking the seal.  BTW I had a bulb around
here that got water in it due to a busted pipe in the ceiling and it still
lit up until the leak stopped and the bulb sucked air instead of water.
Pretty weird, huh?

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email EraseMElistservspamEraseMEmitvma.mit.edu with SET PICList DIGEST in the body


2001\06\29@132242 by Roman Black

flavicon
face
Dan Michaels wrote:
{Quote hidden}

Ha ha! Remember their income comes from selling
you replacement light bulbs...

I measured some 60w 240vac bulbs here, their cold
resistance was 50 to 60 ohms. You work it out! :o)
-Roman

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email @spam@listserv@spam@spamspam_OUTmitvma.mit.edu with SET PICList DIGEST in the body


'[OT]: Priority Green was Modulating a headlight'
2001\06\29@134837 by Dan Michaels

flavicon
face
MB wrote:

>>
>> It used to be, in Boulder, if you were the 1st guy at the light,
>> and peeled off when it turned green, and drove 15 MPH over the
>> limit, you could just make it through the next light. Unfortunately,
>> the city caught on to us getting away with this.
>
>This sounds like some of the long straight main roads running outside of
>downtown.

..... this was from one block to the next downtown!

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email spamBeGonelistservspamKILLspammitvma.mit.edu with SET PICList DIGEST in the body


'[EE]: Modulating a headlight'
2001\06\29@161109 by David VanHorn

flavicon
face
At 12:13 PM 6/29/01 -0500, michael brown wrote:
> > And, of course, my 100W GE light bulbs always seems to
> > go pffffft right when I turn on the light switch. I am
> > sure that GE designs the cold resistance of the filaments
> > in such as way as to maximize the retirement payoff for
> > Jack Welch
>Part of the problem is that the vacuum "leaked out ;-D" the last time you
>turned it off and it cooled, breaking the seal.  BTW I had a bulb around
>here that got water in it due to a busted pipe in the ceiling and it still
>lit up until the leak stopped and the bulb sucked air instead of water.
>Pretty weird, huh?

They don't actually have a vaccum.
Argon or nitrogen I think, but there's no nothing there.

--
Dave's Engineering Page: http://www.dvanhorn.org

I would have a link to http://www.findu.com/cgi-bin/find.cgi?KC6ETE-9 here
in my signature line, but due to the inability of sysadmins at TELOCITY to
differentiate a signature line from the text of an email, I am forbidden to
have it.

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email .....listservspam_OUTspammitvma.mit.edu with SET PICList DIGEST in the body


'[OT]: Priority Green was Modulating a headlight'
2001\06\29@191417 by M. Adam Davis

flavicon
face
That's interesting.  So the lights are red on all sides for 80% of the
time, and each way is given 10% of the remaining time for green and yellow?

;-)

-Adam

michael brown wrote:

{Quote hidden}

>{Original Message removed}

2001\06\29@194616 by michael brown

flavicon
face
> That's interesting.  So the lights are red on all sides for 80% of the
> time, and each way is given 10% of the remaining time for green and
yellow?
>
> ;-)
>
> -Adam
Of course not silly. ;-D  The lights are synchronized to something, just not
sure what.  The light will be green as you are approaching and invariably
changes as you get closer.  No kidding, it really is annoying.  Come on down
and see for yourself, you won't like it.  I promise. ;-D

michael

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email TakeThisOuTlistserv.....spamTakeThisOuTmitvma.mit.edu with SET PICList DIGEST in the body


2001\06\29@221001 by Dan Michaels

flavicon
face
>Of course not silly. ;-D  The lights are synchronized to something, just not
>sure what.  The light will be green as you are approaching and invariably
>changes as you get closer.  No kidding, it really is annoying.  Come on down
>and see for yourself, you won't like it.  I promise. ;-D
>

Nowadays, in Boulder, many lights have either CCD cams or speed
sensors. The CCDs photo ID people running the red, and the speed
sensors actually trip the green to red if the cars approaching
are going too fast. In betweenst, we have photo radar units
in unmarked vans sitting around here and there. [geez, I read
about places like this in books when I was growing up].

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email TakeThisOuTlistservKILLspamspamspammitvma.mit.edu with SET PICList DIGEST in the body


2001\06\29@233557 by goflo

flavicon
face
In the San Diego area we've had a red-light photo enforcement
for several years now - $271 fine, 40/60 split between the
city & Lockheed-Martin, which provides the equipment, fingers
the presumptively guilty.
In practice the cameras are installed at high volume intersections
(not high-accident intersections), and the yellow-light times are
reduced to enhance the take.
I'm a bicyclist - If there's an up side to motorists running lights
I've missed it, but the scheme ignores the common, deadly practice
of motorists turning right on red without slowing down, much less
stopping - Turning right, looking left...

Jack

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email .....listservspamRemoveMEmitvma.mit.edu with SET PICList DIGEST in the body


'[EE]: Modulating a headlight'
2001\06\30@042721 by Roman Black

flavicon
face
David VanHorn wrote:
>
> At 12:13 PM 6/29/01 -0500, michael brown wrote:
> > > And, of course, my 100W GE light bulbs always seems to
> > > go pffffft right when I turn on the light switch. I am
> > > sure that GE designs the cold resistance of the filaments
> > > in such as way as to maximize the retirement payoff for
> > > Jack Welch
> >Part of the problem is that the vacuum "leaked out ;-D" the last time you
> >turned it off and it cooled, breaking the seal.  BTW I had a bulb around
> >here that got water in it due to a busted pipe in the ceiling and it still
> >lit up until the leak stopped and the bulb sucked air instead of water.
> >Pretty weird, huh?
>
> They don't actually have a vaccum.
> Argon or nitrogen I think, but there's no nothing there.


Low pressure nitrogen in most bulbs. It is less than
atmospheric pressure but far from a "vacuum".
Put a light bulb in a water filled container and pop
it? Should give a rough idea of the pressure inside.
-Roman

--
http://www.piclist.com hint: To leave the PICList
RemoveMEpiclist-unsubscribe-requestspamspamBeGonemitvma.mit.edu


2001\06\30@044405 by Peter L. Peres

picon face
You can use a N-VFET (cheap, easy to get) and a charge pump and level
converter to shift the 12V to something the high side mounted FET can use.
I did it that way once and it works well. The charge pump used an existing
square wave signal and a number of CMOS gates in parallel. The level
shifter was a section of a LM324 opamp wired as DC amp with gain x10 or
so. My switching frequency was 1000Hz. This was for a motor. The noise was
a welcome addition (warning noise).

Peter

--
http://www.piclist.com hint: To leave the PICList
spamBeGonepiclist-unsubscribe-request@spam@spamspam_OUTmitvma.mit.edu


2001\06\30@060713 by Jinx

face picon face
> >> And, of course, my 100W GE light bulbs always seems to
> >> go pffffft right when I turn on the light switch. I am

> Roman, fantastic, so 5% is all it takes?

An update - it's been around 5 months since I added 47R 10W
resistors to my 240VAC wall lights, and so far not one has blown.
Based on the previous couple of years by now I would have
expected several, if not all, of them to have popped at turn on.
The ones with 2x47R resistors are only very slightly yellower but
you can't really notice that because of the shades

http://home.clear.net.nz/pages/joecolquitt/0bulblife.html

--
http://www.piclist.com hint: To leave the PICList
TakeThisOuTpiclist-unsubscribe-requestspamspammitvma.mit.edu


'[OT]: Priority Green was Modulating a headlight'
2001\06\30@061759 by Peter L. Peres

picon face
> It used to be, in Boulder, if you were the 1st guy at the light,
> and peeled off when it turned green, and drove 15 MPH over the
> limit, you could just make it through the next light. Unfortunately,
> the city caught on to us getting away with this.

Please tell me that you are not serious about the city setting the lights
*deliberately* to cause traffic slowdowns ?

Peter

--
http://www.piclist.com hint: To leave the PICList
piclist-unsubscribe-requestEraseMEspammitvma.mit.edu


'[EE]: Traffic lights, (was Modulating a headlight)'
2001\06\30@062646 by Roman Black

flavicon
face
There is an entire science of city traffic lights and
traffic flow control. A friend of mine worked for the
city department, he told me all the lights now are on
their own modems, and they can upload new timing specs
to any lights controller from the office.

The lights controllers have a 24hour + 7day real time
clock and give priorities to different traffic flow
directions at different times of day and different days
of the week, like friday afternoon rush hour etc.

His job was to go and place those rubber tubes and
dataloggers on the road, then collect them and enter
the data into the office computer. Then they do
simulations (looks a bit like simcity he said!) and
test different lights timings for the known traffic
flows. All very cool stuff, and they even have a
psychology guy there too. If most of your lights are
always red they do this deliberately to encourage
drivers to choose an alternate route. You need to
find it! :o)

Also, I read on a motorcycle list that the makers of
redlight (traffic fine) cameras in the UK signed a
deal with the local council that light timings are not
allowed to be changed there and the camera maker gets
a % cut of the traffic fines. It's causing a bit of
hoo-haa with the drivers there...
-Roman

--
http://www.piclist.com hint: To leave the PICList
RemoveMEpiclist-unsubscribe-requestEraseMEspamspam_OUTmitvma.mit.edu


'[EE]: Modulating a headlight'
2001\06\30@072649 by jeethur

flavicon
face
That sounds like a good addition to my Car.

The only question, Does it work only in the US or the whole of the World ?
Because I live in India.

Jeethu Rao

{Original Message removed}

2001\06\30@072657 by jeethur

flavicon
face
Hi Bob,

Is'nt 12 volts sufficient to drive the MOSFET ?

How about the PIC driving a small NPN transistor like BC548 or 2N2222
And you can connect the collector to the 12 v supply and drive the Gate
of the FET through a 10 Ohms Resistor ?

I had posted a message yesterday with a similar schematic.
Its titled "Re: [EE]: Driving a BUZ10 Mosfet"

Is there something wrong with this method ?

Jeethu Rao


{Original Message removed}

2001\06\30@074728 by Peter L. Peres

picon face
> bulb with water still working

Bulbs are not 'filled' with vacuum, but with a mixture of non-active
gases, among them Argon and Nitrogen, at low (but not vacuum) pressure. As
long as there is no Oxygen in the bulb the filament will continue to work,
but the heat losses will become enormous so it will be much dimmer. This
is not true for very small bulbs which are indeed vacummed.

Peter

--
http://www.piclist.com hint: To leave the PICList
@spam@piclist-unsubscribe-requestRemoveMEspamEraseMEmitvma.mit.edu


'[OT]: Priority Green was Modulating a headlight'
2001\06\30@100431 by Dale Botkin

flavicon
face
On Fri, 29 Jun 2001, Dan Michaels wrote:

> >Of course not silly. ;-D  The lights are synchronized to something, just not
> >sure what.  The light will be green as you are approaching and invariably
> >changes as you get closer.  No kidding, it really is annoying.  Come on down
> >and see for yourself, you won't like it.  I promise. ;-D
> >
>
> Nowadays, in Boulder, many lights have either CCD cams or speed
> sensors. The CCDs photo ID people running the red, and the speed
> sensors actually trip the green to red if the cars approaching
> are going too fast. In betweenst, we have photo radar units
> in unmarked vans sitting around here and there. [geez, I read
> about places like this in books when I was growing up].

You know, I sure do wish they'd trade all the stealth spy crap for a few
more plainly marked police cars and some more open enforcement.  The
electronics only addresses one issue -- speeding/red lights/whatever.  A
cruiser can do so much more to keep the peace.

Dale
--
A train stops at a train station.  A bus stops at a bus station.
On my desk I have a workstation...

--
http://www.piclist.com hint: To leave the PICList
EraseMEpiclist-unsubscribe-requestspam@spam@mitvma.mit.edu


'[EE]: Modulating a headlight'
2001\06\30@100846 by Chris Carr

flavicon
face
> That sounds like a good addition to my Car.
>
> The only question, Does it work only in the US or the whole of the World ?
> Because I live in India.
>
> Jeethu Rao
>
Well it won't work in the UK as a different method is used which doesn't
involve light.

Chris Carr
>
>
>
> Back it down to 14hz and you can trip all the Priority Green systems here
> in the US... have a green light everywhere you go!!! (and alot of other
mad
> drivers!!!).  Of course, this is probably illegal.
>
> Scott F. Touchton
> 1550 Engineering Manager
> JDS Uniphase
>
>

--
http://www.piclist.com hint: To leave the PICList
@spam@piclist-unsubscribe-requestspam_OUTspam.....mitvma.mit.edu


2001\06\30@102811 by Anders_Mejl=E6nder_Jakhelln?=

flavicon
face
I don't know if this has been suggested, but you can try to drive the P-Channel FET via Opto Coupler, and in the "off period" simply use PWM so that the filament will stay a bit warmer than turning it completely off.

Anders

{Original Message removed}

'[OT]: Priority Green was Modulating a headlight'
2001\06\30@112234 by michael brown

flavicon
face
> You know, I sure do wish they'd trade all the stealth spy crap for a few
> more plainly marked police cars and some more open enforcement.  The
> electronics only addresses one issue -- speeding/red lights/whatever.  A
> cruiser can do so much more to keep the peace.
>
> Dale

I hear you on that!  This modern "enforcement" is nothing more than a new
taxation technique.  I think police cars also shouldn't have air
conditioning or "good time" radios.  It's hard to know what's going on
around you when you are zipping around with the windows up and a/c blasting
all while jamming to the radio.

If I were a police officer I would make a point of never writing a speeding
ticket unless it was for something actually dangerous.  But I would make
people well aware of the rest of the traffic laws, like signals and sudden
lane swerving (I ride a motorcycle and I would like to live).

On the motorcycle thing, I would like to take this opportunity to make
everyone aware that motorcycles can NOT stop quicker than cars.  This is a
common misnomer that has resulted in the death of many cyclists.  PLEASE,
the next time you change lanes please turn your head and look first.  Fully
95% of my "close calls" have been a result of this.  Of course when they
finally see you, they nearly always wave and say sorry.  This is a prime
example of where being "sorry" doesn't help.

BTW the other day I was nearly run over by a police car (with no lights or
siren) that was busy running a red light that had been red the entire time
he was approaching it.  Fortunately, I have learned to not trust anyone in a
car that isn't looking me directly in the eye.  Next time you see/hear a
Harley with loud exhaust, remember he is just trying to stay alive, not
annoy/scare you.  Loud pipes allow you to become semi-transparent as opposed
to the normal complete invisibility that a motorcycle achieves when riding
in traffic.

Oops ranting again.

michael (with his silly utopian ideas)

--
http://www.piclist.com hint: To leave the PICList
spamBeGonepiclist-unsubscribe-requestEraseMEspammitvma.mit.edu


2001\06\30@113942 by goflo

flavicon
face
Peter L. Peres wrote:

> Please tell me that you are not serious about the city
> setting the lights *deliberately* to cause traffic slowdowns ?

Peter, my dear fellow! %)

The agencies involved have absolutely no incentive to
address the problem - Their very existence depends on
the gridlock - The municipalities cooperate by allowing
development which outruns road capacity in multiples,
the road-builders use the snarl to get public support
for construction bonds for projects which will be tied
up in court for 20+ years, and feast on the float in the
interim - Everybody's happy, except the chumps in the cars...

Since others have alluded to the "science" of traffic
management, it is a fact that the supply of vehicles
increases faster than carrying capacity of the roads,
most places - Certainly here in the PRC. This has been
studied to death, and the obvious ramifications being
unpalatable, resolutely ignored.

best regards, Jack

--
http://www.piclist.com hint: To leave the PICList
piclist-unsubscribe-requestspamBeGonespammitvma.mit.edu


2001\06\30@150324 by Dan Michaels

flavicon
face
Peter Peres wrote:
>> It used to be, in Boulder, if you were the 1st guy at the light,
>> and peeled off when it turned green, and drove 15 MPH over the
>> limit, you could just make it through the next light. Unfortunately,
>> the city caught on to us getting away with this.
>
>Please tell me that you are not serious about the city setting the lights
>*deliberately* to cause traffic slowdowns ?
>

Not to worry, Peter. Only in Boulder are the control freaks
running the govt. Feel better now?

[BTW, they only wish to rein in the guys that drive like
Roman and me].

- dan
==================

--
http://www.piclist.com hint: To leave the PICList
RemoveMEpiclist-unsubscribe-request@spam@spamspamBeGonemitvma.mit.edu


'[EE]: Modulating a headlight'
2001\06\30@152155 by George Tyler

flavicon
face
Be careful: Halogen light don't like to run to cold!

----- Original Message -----
From: Anders Mejlænder Jakhelln <.....anders@spam@spamEraseMEJAKHELLN.NO>
To: <.....PICLISTRemoveMEspamMITVMA.MIT.EDU>
Sent: Saturday, June 30, 2001 4:26 PM
Subject: Re: [EE]: Modulating a headlight


I don't know if this has been suggested, but you can try to drive the
P-Channel FET via Opto Coupler, and in the "off period" simply use PWM so
that the filament will stay a bit warmer than turning it completely off.

Anders

----- Original Message -----
From: "Miles McKinnon" <.....miles.piclistSTOPspamspam@spam@home.com>
To: <PICLISTEraseMEspam@spam@MITVMA.MIT.EDU>
Sent: Friday, June 29, 2001 12:27 AM
Subject: [EE]: Modulating a headlight


> I am building a motorcycle headlight modulator using a PIC to monitor
> ambient light and a few other things.  Anyway, the PIC has to modulate the
> headlight ( ~ 4Amps) at a arount 240Hz or so.
>
> There are a few legal stipulations.  They say that you cannot switch the
> ground, you must switch the +12V to the headlight.  I want to use a low
Rds
{Quote hidden}

--
http://www.piclist.com hint: To leave the PICList
RemoveMEpiclist-unsubscribe-requestspamspamBeGonemitvma.mit.edu

--
http://www.piclist.com hint: To leave the PICList
spamBeGonepiclist-unsubscribe-requestKILLspamspam@spam@mitvma.mit.edu


'[OT]: Priority Green was Modulating a headlight'
2001\06\30@171732 by Matt Bennett

flavicon
face
michael brown wrote:

> On the motorcycle thing, I would like to take this opportunity to make
> everyone aware that motorcycles can NOT stop quicker than cars.  This is a
> common misnomer that has resulted in the death of many cyclists.  PLEASE,
> the next time you change lanes please turn your head and look first.  Fully
> 95% of my "close calls" have been a result of this.  Of course when they
> finally see you, they nearly always wave and say sorry.  This is a prime
> example of where being "sorry" doesn't help.
>
> BTW the other day I was nearly run over by a police car (with no lights or
> siren) that was busy running a red light that had been red the entire time
> he was approaching it.  Fortunately, I have learned to not trust anyone in a
> car that isn't looking me directly in the eye.  Next time you see/hear a
> Harley with loud exhaust, remember he is just trying to stay alive, not
> annoy/scare you.  Loud pipes allow you to become semi-transparent as opposed
> to the normal complete invisibility that a motorcycle achieves when riding
> in traffic.

As a Piclister and a motorcyclist (7 motorcycles in the garage, and I've
been a Motorcycle Safety Instructor for 6 years), I feel obliged to
respond.  Loud pipes are not an effective safety device- unfortunately,
most of the "loud" goes *behind* the motorcycle, doing little to wake up
the semi-consious lane changer.  The biggest effect that loud exhausts
are having is to inspire community rules and legislation to ban
motorcycles, which, in my view, is a net loss for motorcycling as a
whole.  I've found that simple things like actively avoiding the blind
spots of other motorists to be a far more effective safety technique.

With the proper technique and practice, on good clean pavement, a
motorcycle *can* stop faster than most cars.  Many motorcycles today
have twin discs on the front wheel, and very sticky tires.  All the
elements above don't necessarily happen at the same time- so avoidance
is the best technique to minimize risk.

Back to the headlight modulating- on-off cycles do decrease the lifetime
of a bulb, but  that is with a cold filament.  Modulating a headlight at
4Hz is slow enough so that the modulation can be seen, but fast enough
so that the filament does not fully cool down.  Try this experiment- at
night, turn your headlights on and point them at a close wall.  Turn
them off- I've found that it takes at least 2 seconds for the bulbs to
stop putting out light.  The very bright, white light stops almost
immediately, but it keeps on putting out light for some time, decreasing
in intensity and moving to red before it fades out completely.

Matt Bennett

--
http://www.piclist.com hint: To leave the PICList
piclist-unsubscribe-requestspam_OUTspam@spam@mitvma.mit.edu


2001\06\30@173611 by Dan Michaels

flavicon
face
>michael brown wrote:
>
>> On the motorcycle thing, I would like to take this opportunity to make
>> everyone aware that motorcycles can NOT stop quicker than cars.  This is a
>> common misnomer that has resulted in the death of many cyclists.  PLEASE,
>> the next time you change lanes please turn your head and look first.  Fully
>> 95% of my "close calls" have been a result of this.


If you don't know how already, time to learn "countersteering" for
those quick and death situations. Simple physics, what.

Also, when stopping, you do need to learn to use that front brake.
==========


Matt Bennett wrote:
.....
 I've found that simple things like actively avoiding the blind
>spots of other motorists to be a far more effective safety technique.
>

When I used to ride bikes, I found the best way to survive was to
think that every single car in the vicinity was about to do something
that would kill me. This way I wouldn't get into the situations
where it might happen.

--
http://www.piclist.com hint: To leave the PICList
spamBeGonepiclist-unsubscribe-request@spam@spammitvma.mit.edu


2001\06\30@175313 by Matt Bennett

flavicon
face
Dan Michaels wrote:
>
> >michael brown wrote:
> >
> >> On the motorcycle thing, I would like to take this opportunity to make
> >> everyone aware that motorcycles can NOT stop quicker than cars.  This is a
> >> common misnomer that has resulted in the death of many cyclists.  PLEASE,
> >> the next time you change lanes please turn your head and look first.  Fully
> >> 95% of my "close calls" have been a result of this.
>
> If you don't know how already, time to learn "countersteering" for
> those quick and death situations. Simple physics, what.
>
> Also, when stopping, you do need to learn to use that front brake.

If you ride motorcycles or just want to *TAKE THE MSF COURSE* (or an
appropriate safety course for your locality).  If it's been a while
since you've taken it, TAKE IT AGAIN.  I'm not trying to drum up
business- most MSF instruction sites are at capacity anyway, and lord
knows I don't do it for the pay.  Motorcycles are dangerous.
Motorcyclists have to accept the danger, but there are effective
techniques that will help you minimize the danger.  Every time I've
taught the course to experienced riders, the students have told me they
have learned something, even those that have been riding far longer than
I have.

Matt

--
http://www.piclist.com hint: To leave the PICList
RemoveMEpiclist-unsubscribe-requestEraseMEspamKILLspammitvma.mit.edu


2001\06\30@175724 by michael brown

flavicon
face
> michael brown wrote:
>
> > On the motorcycle thing, I would like to take this opportunity to make
> > everyone aware that motorcycles can NOT stop quicker than cars.  This is
a
> > common misnomer that has resulted in the death of many cyclists.
PLEASE,
> > the next time you change lanes please turn your head and look first.
Fully
> > 95% of my "close calls" have been a result of this.  Of course when they
> > finally see you, they nearly always wave and say sorry.  This is a prime
> > example of where being "sorry" doesn't help.
> >
> > BTW the other day I was nearly run over by a police car (with no lights
or
> > siren) that was busy running a red light that had been red the entire
time
> > he was approaching it.  Fortunately, I have learned to not trust anyone
in a
> > car that isn't looking me directly in the eye.  Next time you see/hear a
> > Harley with loud exhaust, remember he is just trying to stay alive, not
> > annoy/scare you.  Loud pipes allow you to become semi-transparent as
opposed
> > to the normal complete invisibility that a motorcycle achieves when
riding
> > in traffic.
>
> As a Piclister and a motorcyclist (7 motorcycles in the garage, and I've
> been a Motorcycle Safety Instructor for 6 years), I feel obliged to
> respond.  Loud pipes are not an effective safety device- unfortunately,
> most of the "loud" goes *behind* the motorcycle, doing little to wake up
> the semi-consious lane changer.

I didn't mean to imply that they were "the" solution to motorcycle safety.
But I must say that they are one more way to increase the awareness of other
motorists.  And, I was only offering an explanation for the reasoning behind
why allot (not all) of cyclests increase the loudness of their pipes.
Fortunately, the sound can be redirected towards the side with turn-outs or
"slash cut" pipes.  Every little thing that you can do to increase awareness
is to the cyclists benefit.  Whether it be modulated headlights, loud pipes,
or strobing brakelights.

>The biggest effect that loud exhausts
> are having is to inspire community rules and legislation to ban
> motorcycles, which, in my view, is a net loss for motorcycling as a
> whole.

While I won't disagree with this, I must say that the media and hollywood
have done more to inspire this kind of behavior from the public and local
communities than loud pipes have.  This is certainly not the intent of most
motorcyclists.

>I've found that simple things like actively avoiding the blind
> spots of other motorists to be a far more effective safety technique.

This is absolutely correct, and would probably be sufficient if people
actually looked in their mirrors before changing lanes.   Also not ever
riding next to or behind semi-truck tires is a good idea.  If they peel on
you, or blow out, you could be in world of hurt.

> With the proper technique and practice, on good clean pavement, a
> motorcycle *can* stop faster than most cars.  Many motorcycles today
> have twin discs on the front wheel, and very sticky tires.

While this may be "strictly" true, not everyone has dual front discs,
optimal tires and road conditions or the required training and experience to
accomplish that.  As you know, the slightest amount of water or oil deposits
on pavement can have a marked effect on stopping ability spefically, and
traction in general.  Also, probably 1/2 of the people you see riding a
motorcycle have less than 5000 miles worth of street riding experience.

> All the
> elements above don't necessarily happen at the same time- so avoidance
> is the best technique to minimize risk.

I can't disagree with this entirely, although in Houston it's pretty darned
hard to avoid being near other traffic.

{Quote hidden}

--
http://www.piclist.com hint: To leave the PICList
.....piclist-unsubscribe-requestspamRemoveMEmitvma.mit.edu


2001\06\30@181426 by Jinx

face picon face
> If you ride motorcycles or just want to *TAKE THE MSF COURSE*
> (or an appropriate safety course for your locality).  If it's been a
> while since you've taken it, TAKE IT AGAIN.  I'm not trying to drum
> up

A piece on the TV news a couple of weeks ago pointed out that the
group of motorcyclists most at risk are the > 45yo men who are
having their second wind. Flush with money, they pick up a machine
that's far bigger and zippier than the one they had 30 years before
and get squished in modern traffic densities or just can't handle the
performance and fall off

--
http://www.piclist.com hint: To leave the PICList
piclist-unsubscribe-requestspam@spam@mitvma.mit.edu


2001\06\30@182333 by Matt Bennett

flavicon
face
michael brown wrote:

> >The biggest effect that loud exhausts
> > are having is to inspire community rules and legislation to ban
> > motorcycles, which, in my view, is a net loss for motorcycling as a
> > whole.
>
> While I won't disagree with this, I must say that the media and hollywood
> have done more to inspire this kind of behavior from the public and local
> communities than loud pipes have.  This is certainly not the intent of most
> motorcyclists.
>

No matter the intent, the effect is clear.  There are communities
throughout the US that ban *all* motorcyles because of the actions of a
few who have modified their motorcycles to get (in my opinion) a false
sense of security.  If you take a look at the "loud pipes," they all say
"for off-highway use only" or something to that effect.  There are many
people that would like to ban motorcycling altogether, I don't want to
give them any extra ammunition.

> > With the proper technique and practice, on good clean pavement, a
> > motorcycle *can* stop faster than most cars.  Many motorcycles today
> > have twin discs on the front wheel, and very sticky tires.
>
> While this may be "strictly" true, not everyone has dual front discs,
> optimal tires and road conditions or the required training and experience to
> accomplish that.

Even with a single front disk and non-optimal tires, you may be suprised
what your motorcycle can actually do, if you use the right technique.
Rarely have I seen the skill of a motorcyclist exceed the capabilities
of his motorcycle.

Matt

P.S.  At the proper time and place, I like loud motorcycles.  I just
think that the volume should be proportional to the power that the bike
is putting out.

--
http://www.piclist.com hint: To leave the PICList
EraseMEpiclist-unsubscribe-requestRemoveMEspamSTOPspammitvma.mit.edu


2001\06\30@182346 by michael brown

flavicon
face
>michael brown wrote:
> >
> >> On the motorcycle thing, I would like to take this opportunity to make
> >> everyone aware that motorcycles can NOT stop quicker than cars.  This
is a
> >> common misnomer that has resulted in the death of many cyclists.
PLEASE,
> >> the next time you change lanes please turn your head and look first.
Fully
> >> 95% of my "close calls" have been a result of this.
>
>
> If you don't know how already, time to learn "countersteering" for
> those quick and death situations. Simple physics, what.

I know how to do this and do it all the time.  It works very nicely for
avoiding holes and what not.

> Also, when stopping, you do need to learn to use that front brake.

DUH!!!!  Come on Dan, you should know me better than that. ;-D  You can't
stop without it.  But I only have one rotor in the front.

{Quote hidden}

That's exactly how it's done.  This will do more than probably anything to
protect you.  Eye contact is also imperative.

--
http://www.piclist.com hint: To leave the PICList
RemoveMEpiclist-unsubscribe-requestKILLspamspamTakeThisOuTmitvma.mit.edu


2001\06\30@182802 by michael brown

flavicon
face
> If you ride motorcycles or just want to *TAKE THE MSF COURSE* (or an
> appropriate safety course for your locality).  If it's been a while
> since you've taken it, TAKE IT AGAIN.  I'm not trying to drum up
> business- most MSF instruction sites are at capacity anyway, and lord
> knows I don't do it for the pay.

These classes are very good, and I highly recommend them.

> Motorcycles are dangerous.

Now come on. ;-)  The biggest dangers concerning motorcycles involve, speed,
alcohol, and mostly cars.

> Motorcyclists have to accept the danger, but there are effective
> techniques that will help you minimize the danger.  Every time I've
> taught the course to experienced riders, the students have told me they
> have learned something, even those that have been riding far longer than
> I have.
>
> Matt

I have been riding for quite a while, but I didn't know about
counter-steering until a few years ago.  It's not the kind of thing that you
would just happen upon thru normal riding.  However, after using it and
gaining experience with it, its become quite natural.

--
http://www.piclist.com hint: To leave the PICList
spamBeGonepiclist-unsubscribe-requestspam@spam@mitvma.mit.edu


2001\06\30@183830 by michael brown

flavicon
face
> michael brown wrote:
>
> > >The biggest effect that loud exhausts
> > > are having is to inspire community rules and legislation to ban
> > > motorcycles, which, in my view, is a net loss for motorcycling as a
> > > whole.
> >
> > While I won't disagree with this, I must say that the media and
hollywood
> > have done more to inspire this kind of behavior from the public and
local
> > communities than loud pipes have.  This is certainly not the intent of
most
{Quote hidden}

I have heard of this and cannot for the life of me understand why a state
government would stand for the banning of a federally approved and state
licensed vehicle on a stated funded road.  I have yet to see that here.

>
> > > With the proper technique and practice, on good clean pavement, a
> > > motorcycle *can* stop faster than most cars.  Many motorcycles today
> > > have twin discs on the front wheel, and very sticky tires.
> >
> > While this may be "strictly" true, not everyone has dual front discs,
> > optimal tires and road conditions or the required training and
experience to
> > accomplish that.
>
> Even with a single front disk and non-optimal tires, you may be suprised
> what your motorcycle can actually do, if you use the right technique.
> Rarely have I seen the skill of a motorcyclist exceed the capabilities
> of his motorcycle.
>
> Matt

I understand your point here, on "dry" pavement I can stop my bike very
quickly.  But on wet pavement it makes a larger difference than cars
experience given the same wet conditions.

> P.S.  At the proper time and place, I like loud motorcycles.  I just
> think that the volume should be proportional to the power that the bike
> is putting out.

I think so too, that's why I'm gonna get my sporty putting out 95 hp at 85
ft/lbs.  That way it will run like it sounds. ;-D  Seriously, my pipes are
on the low side of the loudness range.  However, I have been noticed in
dense traffic and when passing people where they otherwise would never have
known I was there.  I can't say that they didn't hit me because of it, that
would be impossible to prove.  However, I can say that they noticed me
sooner than they otherwise would have.  Plus, on the lighter side, loud
pipes compliment cellular phones nicely. ;-D

--
http://www.piclist.com hint: To leave the PICList
RemoveMEpiclist-unsubscribe-requestspam_OUTspammitvma.mit.edu


2001\06\30@201938 by Dan Michaels

flavicon
face
>> If you don't know how already, time to learn "countersteering" for
>> those quick and death situations. Simple physics, what.
>
>I know how to do this and do it all the time.  It works very nicely for
>avoiding holes and what not.
>

and prairie dogs.
================

>> Also, when stopping, you do need to learn to use that front brake.
>
>DUH!!!!  Come on Dan, you should know me better than that. ;-D  You can't
>stop without it.  But I only have one rotor in the front.
>

Say what? Here's today's quiz, should you use the front brake
to slow down while in a turn? Or will physics toss you on your
ear?
==============

>>
>> When I used to ride bikes, I found the best way to survive was to
>> think that every single car in the vicinity was about to do something
>> that would kill me. This way I wouldn't get into the situations
>> where it might happen.
>
>That's exactly how it's done.  This will do more than probably anything to
>protect you.  Eye contact is also imperative.
>

I assume you mean eye contact with the guy who is coming
in your direction and turning across your path.

Seriously, as I recall the "single" most important safety
factor ever, regarding motorcycles, has been to burn the headlight
in the daytime hours. I recall reading an old safety study that
showed, prior to this, something like 40-50% [forget exactly]
of accidents involved a car turning across the motorcyclist's
path, and the driver later claiming he/she never saw the bike.

So actually I am wondering whether flickering the light is
really all that more effective.

--
http://www.piclist.com hint: To leave the PICList
piclist-unsubscribe-requestspamspammitvma.mit.edu


2001\06\30@202319 by Dan Michaels

flavicon
face
>> P.S.  At the proper time and place, I like loud motorcycles.  I just
>> think that the volume should be proportional to the power that the bike
>> is putting out.
>
>I think so too, that's why I'm gonna get my sporty putting out 95 hp at 85
>ft/lbs.  That way it will run like it sounds. ;-D  Seriously, my pipes are
>on the low side of the loudness range.  However, I have been noticed in
>dense traffic and when passing people where they otherwise would never have
>known I was there.  I can't say that they didn't hit me because of it, that
>would be impossible to prove.  However, I can say that they noticed me
>sooner than they otherwise would have.  Plus, on the lighter side, loud
>pipes compliment cellular phones nicely. ;-D
>

hint - Fiam horns are better.

--
http://www.piclist.com hint: To leave the PICList
spam_OUTpiclist-unsubscribe-requestspam_OUTspamspam_OUTmitvma.mit.edu


2001\06\30@202732 by Dan Michaels

flavicon
face
>> Motorcycles are dangerous.
>
>Now come on. ;-)  The biggest dangers concerning motorcycles involve, speed,
>alcohol, and mostly cars.
>

More so, young guys with cahones bigger than their brains.

--
http://www.piclist.com hint: To leave the PICList
piclist-unsubscribe-requestspam_OUTspammitvma.mit.edu


2001\06\30@210441 by michael brown

flavicon
face
> >> If you don't know how already, time to learn "countersteering" for
> >> those quick and death situations. Simple physics, what.
> >
> >I know how to do this and do it all the time.  It works very nicely for
> >avoiding holes and what not.
> >
>
> and prairie dogs.

LOL  It would be really good for that.

{Quote hidden}

Well.....Under known, quality road conditions, I have used my front brake
when braking before, into and even during a "turn" (usually in curves).  It
works fine, BUT: If you laterally slip that front wheel even a small amount
(and this could happen even without the brake applied), you could end up
with ear trouble. ;-(  Every situation is unique and braking is a reflex
anymore.

> ==============
>
> >>
> >> When I used to ride bikes, I found the best way to survive was to
> >> think that every single car in the vicinity was about to do something
> >> that would kill me. This way I wouldn't get into the situations
> >> where it might happen.
> >
> >That's exactly how it's done.  This will do more than probably anything
to
> >protect you.  Eye contact is also imperative.
> >
>
> I assume you mean eye contact with the guy who is coming
> in your direction and turning across your path.

I wont cross in front of a vehicle that is perpendicular to me until they
look at me, if it can be avoided.  I basically do as you said before, and
treat all other cars as being out to get me (none of them can see me
either).  Another survival tip is to stay out of rush hour traffic as much
as possible, when people are aggressively trying to get home, that is there
#1 goal, and they don't have time to look for bikes.

> Seriously, as I recall the "single" most important safety
> factor ever, regarding motorcycles, has been to burn the headlight
> in the daytime hours. I recall reading an old safety study that
> showed, prior to this, something like 40-50% [forget exactly]
> of accidents involved a car turning across the motorcyclist's
> path, and the driver later claiming he/she never saw the bike.

With the light only 30-40% don't see you. ;-)  Plus, I am a bit skeptical of
what the "survivors" version of events is. ;-D  Seriously though, my "close
encounters" mostly were this type of thing.  Most of the time it has been
someone pulling out onto the street in front of you.  Then the venerable
"houston swerve" lane changes.  Nobody sees you on a motorcycle, that's for
sure.

> So actually I am wondering whether flickering the light is
> really all that more effective.

I think it might be, because I would think that the brain is use to seeing
glares and these are somewhat similar to a constant burning light at a
distance.  But glares usually don't self modulate. ;-D  I would think that
the brain would be much more apt to "notice".  That's just my 2¢.  I'm going
to get one of those "rainbow" effect halogen bulbs.  They are mostly white
light, but with a tinge of color.  I'm hoping that this will improve
visibility.

[EE] content:
    They now have these neat super bright LED "bulb" replacements that fit
in a standard turn signal socket and fit in the same clearances.  They have
some kind of little PIC chip inside that gives a rotating effect to the
cluster of pcboard mounted LED's. They also have a tail light board that
fits inside the regular lens and uses bi-color LED's to do the running, stop
and turn lamps.  They are expensive, you guys should come out with your own
versions.

--
http://www.piclist.com hint: To leave the PICList
RemoveMEpiclist-unsubscribe-requestKILLspamspam@spam@mitvma.mit.edu


'[EE]: Modulating a headlight'
2001\06\30@210717 by Olin Lathrop

face picon face
> An update - it's been around 5 months since I added 47R 10W
> resistors to my 240VAC wall lights, and so far not one has blown.
> Based on the previous couple of years by now I would have
> expected several, if not all, of them to have popped at turn on.
> The ones with 2x47R resistors are only very slightly yellower but
> you can't really notice that because of the shades

You could try compact flourescents.  They take much less power for the same
light output, last about 9 times longer, and they are actually cheaper.  I
knew they were more efficient and lasted longer, but I was surprised to find
they were actually cheaper when I worked it out.  It turns out the bulk of
the cost of an incandescent is the electricity it uses.  Even 9 incandescent
bulbs are cheaper than one compact flourescent, but cost much more in
electricity.  I was using $.11 per kilowatt-hour as the price of
electricity, so your milage may vary, but at that price it wasn't even
close.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olinspamBeGonespam.....embedinc.com, http://www.embedinc.com

--
http://www.piclist.com hint: To leave the PICList
KILLspampiclist-unsubscribe-requestspam.....mitvma.mit.edu


'[OT]: Priority Green was Modulating a headlight'
2001\06\30@211104 by michael brown

flavicon
face
> >> Motorcycles are dangerous.
> >
> >Now come on. ;-)  The biggest dangers concerning motorcycles involve,
speed,
> >alcohol, and mostly cars.
> >
>
> More so, young guys with cahones bigger than their brains.

You got that right.  Those cafe style sport bikes are definitely a big
problem.  I'm surprised at what parents will buy for their kids.  It makes
you wonder if they are really thinking or not.  Allot of the guys around
riding those are about 18-20 yrs old.  They have these "special tricks" they
like to perform around the "cruiser" type bikes. :-(

--
http://www.piclist.com hint: To leave the PICList
spam_OUTpiclist-unsubscribe-requestspamKILLspammitvma.mit.edu


2001\06\30@211314 by michael brown

flavicon
face
> hint - Fiam horns are better.

I was thinking about that after my initial posts.  My horn is fairly loud
for a bike, but I want to get an airhorn or two. ;-)

--
http://www.piclist.com hint: To leave the PICList
RemoveMEpiclist-unsubscribe-requestRemoveMEspamEraseMEmitvma.mit.edu


2001\06\30@212153 by goflo

flavicon
face
Dan Michaels wrote:

> Seriously, as I recall the "single" most important safety
> factor ever, regarding motorcycles, has been to burn the headlight
> in the daytime hours. I recall reading an old safety study that
> showed, prior to this, something like 40-50% [forget exactly]
> of accidents involved a car turning across the motorcyclist's
> path, and the driver later claiming he/she never saw the bike.

Hogwash. Operative word here is "claiming". If you want to get away
with murder in the PRC, simply nail the victim with your vehicle,
being careful not to have beer on your breath.

Jack

--
http://www.piclist.com hint: To leave the PICList
KILLspampiclist-unsubscribe-requestspamspamBeGonemitvma.mit.edu


2001\06\30@213639 by Dan Michaels

flavicon
face
John Gardner wrote:
>Dan Michaels wrote:
>
>> Seriously, as I recall the "single" most important safety
>> factor ever, regarding motorcycles, has been to burn the headlight
>> in the daytime hours. I recall reading an old safety study that
>> showed, prior to this, something like 40-50% [forget exactly]
>> of accidents involved a car turning across the motorcyclist's
>> path, and the driver later claiming he/she never saw the bike.
>
>Hogwash. Operative word here is "claiming". If you want to get away
>with murder in the PRC, simply nail the victim with your vehicle,
>being careful not to have beer on your breath.
>

Well, it may be whitewash, but it sure ain't hogwash. I can
bear witness to how hard it is to see something small and dark
[bikers love black colors] and moving fast, when it is coming
straight at you. Just look a 1/4 mile down the road, at 2 dark
motorcycles, one with headlight burning and one without, and
tell me what you see.

--
http://www.piclist.com hint: To leave the PICList
piclist-unsubscribe-requestspamspammitvma.mit.edu


2001\06\30@215415 by Alan Beeber

picon face
Over on Yahoo.....

http://dailynews.yahoo.com/h/nm/20010630/od/speedtrap_dc_1.html

michael brown wrote:
{Quote hidden}

--
http://www.piclist.com hint: To leave the PICList
RemoveMEpiclist-unsubscribe-requestspamBeGonespamRemoveMEmitvma.mit.edu


2001\06\30@222106 by michael brown

flavicon
face
> Over on Yahoo.....
>
> http://dailynews.yahoo.com/h/nm/20010630/od/speedtrap_dc_1.html
>
Now that's funny.  It couldn't have happened to a nicer bunch. ;-D

--
http://www.piclist.com hint: To leave the PICList
KILLspampiclist-unsubscribe-requestspamBeGonespammitvma.mit.edu


2001\06\30@223530 by David VanHorn

flavicon
face
>
>Well.....Under known, quality road conditions, I have used my front brake
>when braking before, into and even during a "turn" (usually in curves).  It
>works fine, BUT: If you laterally slip that front wheel even a small amount
>(and this could happen even without the brake applied), you could end up
>with ear trouble. ;-(  Every situation is unique and braking is a reflex
>anymore.

BTDT :)
I used to race on bicycles. When you're in a turn so hard that the high
pedal is scraping, you know you're pushing it. I was in one of these, when
the front tire skipped, presumably on a pebble, then folded in half.  That
was about 25 years ago, and the scars are almost gone now.  It was, of
course, the only time I didn't use Michelins.  I've done 70+ on a bicycle,
it's definitely interesting.

--
Dave's Engineering Page: http://www.dvanhorn.org

I would have a link to http://www.findu.com/cgi-bin/find.cgi?KC6ETE-9 here
in my signature line, but due to the inability of sysadmins at TELOCITY to
differentiate a signature line from the text of an email, I am forbidden to
have it.

--
http://www.piclist.com hint: To leave the PICList
@spam@piclist-unsubscribe-requestSTOPspamspam@spam@mitvma.mit.edu



'[OT]: Priority Green was Modulating a headlight'
2001\07\01@002835 by goflo
flavicon
face
Dan Michaels wrote:
>  I can
> bear witness to how hard it is to see something small and dark
> [bikers love black colors] and moving fast, when it is coming
> straight at you. Just look a 1/4 mile down the road, at 2 dark
> motorcycles, one with headlight burning and one without, and
> tell me what you see.

No offense intended, Dan, but killing someone who is legally
operating a vehicle on the public right-of-way requires a bit
more expiation than "I did'nt see him". Even if you did'nt.
I ride daily, and daily have the experience of taking evasive
action in favor of motorists who are preoccupied with cell phones,
kids, pizzas, reading the papers, putting on make-up, and of course
those who see me just fine, and figure I'll get out of their way -
If I don't, Oh well...

regards, Jack

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@002845 by goflo

flavicon
face
David VanHorn wrote:

> I've done 70+ on a bicycle, it's definitely interesting.

Woo Hoo - I've gotten circa 60 mph - Scared sh*tless.

regards, Jack

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@002850 by Matt Bennett

flavicon
face
Dan Michaels wrote:
>
> Say what? Here's today's quiz, should you use the front brake
> to slow down while in a turn? Or will physics toss you on your
> ear?

I took a roadracing course with Jason Pridmore, and he braked heavily
with the front on every turn, all the way to the apex of the turn, where
he started to accelerate.  How do I know this?  I rode along with him on
the back of his motorcycle. It was simply amazing.  Jason was able to
modulate the throttle very smoothly, along with the brakes, so as not to
abruptly change the geometry of the motorcycle, and upset the
suspension.  Watching a true master at work is awe-inspiring, weather it
is amazingly fast riding, or the beauty of a fine crafted piece of code.

When you do brake in a turn, you've gotta be careful, because a lot of
the available traction is being used to turn the motorcycle.  When you
use up all available traction, the results are... catastrophic.  Because
of the way motorcycle suspensions are set up, braking in a turn will
change the geometry of the motorcycle, and the way it reacts.
Smoothness is key.

Matt

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@003516 by David VanHorn

flavicon
face
At 09:49 PM 6/30/01 -0700, John Gardner wrote:
>David VanHorn wrote:
>
> > I've done 70+ on a bicycle, it's definitely interesting.
>
>Woo Hoo - I've gotten circa 60 mph - Scared sh*tless.

On one run, I melted a set of brake pads, right down to the metal, when I
realized that I was a bit close to the intersection, and the light was red.
I was young and invulnerable then. :)

--
Dave's Engineering Page: http://www.dvanhorn.org

I would have a link to http://www.findu.com/cgi-bin/find.cgi?KC6ETE-9 here
in my signature line, but due to the inability of sysadmins at TELOCITY to
differentiate a signature line from the text of an email, I am forbidden to
have it.

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


'[EE]: Modulating a headlight'
2001\07\01@004630 by Jinx

face picon face
> You could try compact flourescents

Olin, I considered replacing filaments with fluorescents for just
the reasons you outlined. It does make sense (although some
people just don't like them). I have to admit to some out and
out bloody-mindedness with the filament bulbs - I just got so
sick of the damn things blowing I just had to try something and
"get my own back". So far the resistors have been a very good
investment

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


'[OT]: Priority Green was Modulating a headlight'
2001\07\01@011031 by Dan Michaels

flavicon
face
Matt Bennett wrote:
>Dan Michaels wrote:
>>
>> Say what? Here's today's quiz, should you use the front brake
>> to slow down while in a turn? Or will physics toss you on your
>> ear?
>
>I took a roadracing course with Jason Pridmore, and he braked heavily
>with the front on every turn, all the way to the apex of the turn, where
>he started to accelerate.
...........


Well, shoot, you're no fun. I was asking MB ;-).

My understanding is std practice is to brake in the turn, so long
as all of the usual "fun scary" things are absent [gravel, wetness,
dead cats, 2x4's, etc]. BTW, I had my fun hitting gravel in a
hairpin turn once [spent a week every nite in the tub with a set
of tweezers after that], and a 2x4 on a freeway offramp. Course,
my buddy was hit from behind by a pickup truck on a freeway
offramp, so I'm not complaining.

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@011911 by Dale Botkin

flavicon
face
I gotta tell you guys...  it's been years since I was on a bike (assorted
400 vertical twins), and I was thinking seriously about looking at a
newer, larger bike for cruising with the wife...

until today.

On Sun, 1 Jul 2001, Dan Michaels wrote:

{Quote hidden}

--
A train stops at a train station.  A bus stops at a bus station.
On my desk I have a workstation...

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@031142 by Roman Black

flavicon
face
Matt Bennett wrote:
>
> Dan Michaels wrote:
> >
> > Say what? Here's today's quiz, should you use the front brake
> > to slow down while in a turn? Or will physics toss you on your
> > ear?


Ha ha! Is this still the Piclist?? Has one of my
motorcycle mailing lists corrupted my mail server?
;o)

Front brake stands the bike up mid turn, rear brake
pulls it around. Having done racing schools and much
track time myself I believe that anyone with a bike
should at least do the safety course, and an advanced
riding course. And stay away from braking in the
corners unless you are racing.

As for braking abilities of bikes vs cars, it depends
on the bike and rider. My bike from the factory does
60mph to stopped in 2.99 seconds, and it is further
modified now with braided stainless lines and sintered
racing pads. Yes is stops better than a Harley.

As one of those people with a "cafe racer" bike that
is also loud, please don't generalise us! I ride real
safe around people, and the loud pipes bring appreciation
when a concerned parent hears you slowing right down
as you near their child on his wobbly bicycle. As do
cops who hear you gently weaving through traffic. Loud
pipes carry a level of honesty in city riding. If you
start riding fast, everyone knows. I also agree with
the stupid teenager thing, many are not fit to ride
a motorcycle and give all other riders a bad name.
:o)
-Roman

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


'[EE]: Modulating a headlight'
2001\07\01@110927 by Alexandre Domingos F. Souza

flavicon
face
>And I wonder - are the guys selling bulbs outside the US
>mainly subsidiaries of american conglomerates like GE?
>This would explain a lot.

       Yep...GE, Philips, Sylvania, etc.


---8<---Corte aqui---8<----

Alexandre Souza
taitospamBeGonespamspamBeGoneterra.com.br
http://planeta.terra.com.br/lazer/pinball/

---8<---Corte aqui---8<----

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


'[OT]: Priority Green was Modulating a headlight'
2001\07\01@112413 by Alexandre Domingos F. Souza

flavicon
face
>As a Piclister and a motorcyclist (7 motorcycles in the garage, and I've

       Do you ride THAT many? One for each day of the week? :o)


---8<---Corte aqui---8<----

Alexandre Souza
spamBeGonetaitospamterra.com.br
http://planeta.terra.com.br/lazer/pinball/

---8<---Corte aqui---8<----

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@113039 by Matt Bennett

flavicon
face
"Alexandre Domingos F. Souza" wrote:
>
> >As a Piclister and a motorcyclist (7 motorcycles in the garage, and I've
>
>         Do you ride THAT many? One for each day of the week? :o)
>

Do you use every tool in your toolbox every day?

;)

Matt

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@113703 by Alexandre Domingos F. Souza

flavicon
face
>> >As a Piclister and a motorcyclist (7 motorcycles in the garage, and I've
>>         Do you ride THAT many? One for each day of the week? :o)
>Do you use every tool in your toolbox every day?

       No, but surely I don't have 7 multitesters or scopes :o)


---8<---Corte aqui---8<----

Alexandre Souza
spam_OUTtaitoSTOPspamspamterra.com.br
http://planeta.terra.com.br/lazer/pinball/

---8<---Corte aqui---8<----

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@120307 by Bob Barr

picon face
"Alexandre Domingos F. Souza" wrote:

>
> >> >As a Piclister and a motorcyclist (7 motorcycles in the garage, and
>I've
> >>         Do you ride THAT many? One for each day of the week? :o)
> >Do you use every tool in your toolbox every day?
>
>         No, but surely I don't have 7 multitesters or scopes :o)
>

But you've probably got more than 7 screwdrivers and more than 7 wrenches.
:=)

_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


'[EE]: Modulating a headlight'
2001\07\01@122810 by michael brown

flavicon
face
You all might be interested in this info.  http://www.kisantech.com has headlamp
modulators and they claim to use a P-channel mosfet using current regulation
for the modulation.  150 watts maximum.  It's a very small package that
modulates current between 100% and 13% (I guess so the filament doesn't cool
too much)  It also has a light sensor to deactivate the modulation upon
entering a tunnel or darkness.  Pretty neat product, but cost's way too
much. $100.00 for single bulb setup.

You might also be interested in the tireAlert pressure monitoring system.
Uses unpowered device that is attached to the wheel to sense tire pressure.
They claim 1 psi accuracy.  I think that you would have to have the tires
rebalanced after installation.

Any ideas on how the unpowered sending unit functions?  I'm guessing some
kind of internal coil or LC resonant tank.

There's a pretty good market for these kinds of "gadgets".  Bikers love to
spend money on bike toys.  Toys that help you to be seen are very popular.

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@124050 by Spehro Pefhany

picon face
At 11:25 AM 7/1/01 -0500, you wrote:
>You all might be interested in this info.  http://www.kisantech.com has headlamp
>modulators and they claim to use a P-channel mosfet using current regulation
>for the modulation.  150 watts maximum.  It's a very small package that
>modulates current between 100% and 13% (I guess so the filament doesn't cool
>too much)  It also has a light sensor to deactivate the modulation upon
>entering a tunnel or darkness.

If you read the relevant standard that someone posted a link to, the
light sensor is a required feature. It must also have a way of bypassing
the modulator (presumably a mechanical switch) in case of failure.

Best regards,


=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Spehro Pefhany --"it's the network..."            "The Journey is the reward"
RemoveMEspeffspamspaminterlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
Contributions invited->The AVR-gcc FAQ is at: http://www.bluecollarlinux.com
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


'[OT]: Priority Green was Modulating a headlight'
2001\07\01@130731 by Dan Michaels

flavicon
face
Roman Black wrote:
>Matt Bennett wrote:
>>
>> Dan Michaels wrote:
>> >
>> > Say what? Here's today's quiz, should you use the front brake
>> > to slow down while in a turn? Or will physics toss you on your
>> > ear?
>
>
>Ha ha! Is this still the Piclist?? Has one of my
>motorcycle mailing lists corrupted my mail server?
>;o)
>

Ha, Roman, I knew you couldn't resist this discussion.
And it's that new guy, Michael.B, what started this.
;-)
====================

>Front brake stands the bike up mid turn, rear brake
>pulls it around.

Woof. I'll remember that next time I need to juke the bike
sideways 6" fast in the middle of a turn. Inhale. Hand brake
hard, right pedal real hard. Exhale. Woof.
==============

Having done racing schools and much
>track time myself I believe that anyone with a bike
>should at least do the safety course, and an advanced
>riding course. And stay away from braking in the
>corners unless you are racing.
>

I think hereabouts they say you should basically use the
front brake in a turn, just as you would on the straights,
but this is obviously open to discussion ..... and like
everything else on a bike, must be exercised by a calm mind
and moderated by experience.

[BTW, Dale, a "mature" friend of mine who has never ridden,
and is apparently trying to recapture his misspent youth, asked
me a few days ago about the idea of his getting a bike. I just
said "no"].

- danM
===============

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@135427 by michael brown

flavicon
face
----- Original Message -----
From: "Dan Michaels" <TakeThisOuToricomspamspamRemoveMEUSWEST.NET>
To: <KILLspamPICLISTspamspamspam_OUTMITVMA.MIT.EDU>
Sent: Sunday, July 01, 2001 12:07 PM
Subject: Re: [OT]: Priority Green was Modulating a headlight


{Quote hidden}

Hey.....I'm not that new, I've been here three whole months. ;-D  I'm trying
to get over my shyness. ;-)

{Quote hidden}

I don't think just bearing down on the front brake would be a real good
idea, but a "balanced" application of both seems to work well.  A technical
analysis of this "balance"  is difficult because the PID control is almost a
reflex action made up of so many variables and controls. ;-)

> [BTW, Dale, a "mature" friend of mine who has never ridden,
> and is apparently trying to recapture his misspent youth, asked
> me a few days ago about the idea of his getting a bike. I just
> said "no"].
>
> - danM

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@135829 by Dale Botkin

flavicon
face
On Sun, 1 Jul 2001, Dan Michaels wrote:

> [BTW, Dale, a "mature" friend of mine who has never ridden,
> and is apparently trying to recapture his misspent youth, asked
> me a few days ago about the idea of his getting a bike. I just
> said "no"].

I'm not worried about my abilities...  but it sounds like traffic has
gotten a lot worse since the last time I rode (c.  1981 or so).  Not sure
I want to be a target ALL the time.  Maybe I'll stick to flying, it sounds
a lot safer.

Dale
--
A train stops at a train station.  A bus stops at a bus station.
On my desk I have a workstation...

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


'[EE]: Modulating a headlight'
2001\07\01@142218 by Bob Ammerman

picon face
To bring this thread closed to where it started...

While playing with me son with his model railroad I noticed the unusal
headlamp modulation on the locomotive. It uses what is called a MARS light
which alternates between a left and a right filament and appears to shift
back and forth.

Something like this on a motorcycle would certainly be noticed by day (and
then perhaps just turn on both at night.)

Bob Ammerman
RAm Systems
(contract development of high performance, high function, low-level
software)

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@145116 by Chris Carr

flavicon
face
> >And I wonder - are the guys selling bulbs outside the US
> >mainly subsidiaries of american conglomerates like GE?
> >This would explain a lot.
>
>         Yep...GE, Philips, Sylvania, etc.
>
>
Actually the headquarters of Philips is not in the United States of America
but in the United States of Socialist Europe, to be more precise Holland. So
it's a European not an American Conglomerate.

8-)

Chris Carr

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


'[OT]: Priority Green was Modulating a headlight'
2001\07\01@163709 by Dan Michaels

flavicon
face
Dale.B wrote:
>On Sun, 1 Jul 2001, Dan Michaels wrote:
>
>> [BTW, Dale, a "mature" friend of mine who has never ridden,
>> and is apparently trying to recapture his misspent youth, asked
>> me a few days ago about the idea of his getting a bike. I just
>> said "no"].
>
>I'm not worried about my abilities...  but it sounds like traffic has
>gotten a lot worse since the last time I rode (c.  1981 or so).  Not sure
>I want to be a target ALL the time.  Maybe I'll stick to flying, it sounds
>a lot safer.
>

Also, you may want to do some soul searching first, if planning
to get one to take the wife touring. If she's an old biker mama,
then non problemo, but if not, well ..... at least get yourself
a good big insurance policy first [she'll probably only get on the
bike once, and will want some kind of support after you're gone.

[BTW, the mountains west of Denver here are littered with small
plane wrecks too].

- dan
===========

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


'[EE]: Modulating a headlight'
2001\07\01@210423 by Robert A. LaBudde

flavicon
face
At 07:48 PM 7/1/01 +0100, Denis wrote:
>Actually the headquarters of Philips is not in the United States of America
>but in the United States of Socialist Europe, to be more precise Holland. So
>it's a European not an American Conglomerate.

I thought, as Hercule Poirot might have said, "It's a Belgie, not a Dutchie!"

================================================================
Robert A. LaBudde, PhD, PAS, Dpl. ACAFS  e-mail: ralRemoveMEspamlcfltd.com
Least Cost Formulations, Ltd.            URL: http://lcfltd.com/
824 Timberlake Drive                     Tel: 757-467-0954
Virginia Beach, VA 23464-3239            Fax: 757-467-2947

"Vere scire est per causas scire"
================================================================

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\01@222427 by Russell McMahon

picon face
> > >And I wonder - are the guys selling bulbs outside the US
> > >mainly subsidiaries of american conglomerates like GE?
> > >This would explain a lot.
> >
> >         Yep...GE, Philips, Sylvania, etc.
> >
> >
> Actually the headquarters of Philips is not in the United States of
America
> but in the United States of Socialist Europe, to be more precise Holland.
So
> it's a European not an American Conglomerate.


Excuse the probably incorrect spelling - it was (is?) "Philps Gloeilampen
Fabriken" so the link to lightbulbs is a time honoured one.

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\02@132831 by D. Schouten

flavicon
face
> > Actually the headquarters of Philips is not in the United States
of
> America
> > but in the United States of Socialist Europe, to be more precise
Holland.
> So
> > it's a European not an American Conglomerate.
>
>
> Excuse the probably incorrect spelling - it was (is?) "Philps
Gloeilampen
> Fabriken" so the link to lightbulbs is a time honoured one.

'Philips Gloeilampen Fabrieken'. Philips HQ is in Eindhoven The
Netherlands. Although I'm quite sure the lightbulbs aren't
manufactured in The Netherlands anymore (only special products) due to
high production costs. I know Philips makes lightbulbs in France and
Eastern Europe.

Daniel... (from Philips land :-)

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


'[EE]: Bulb Life (x:Modulating headlight)'
2001\07\02@140140 by Barry Gershenfeld

picon face
>An update - it's been around 5 months since I added 47R 10W
>resistors to my 240VAC wall lights, and so far not one has blown.

Two light bulb preserving ideas:

1. I used to see, in those gift catalogues, a small disc-shaped
device that you put into the base under bulb.  It was a
thermistor, such that the cold resistance was high, and
once the lamp was on it would heat up, drop resistance and
give you full brightness.

2. I have always thought that the one place that X-10 "blew it"
was that you cannot start a dimmer up from zero.  If the things
would turn the lights on using a slow ramp up from "dim", I
think the life of any bulb would be extended.  Maybe the bulb
manufacturers "influenced" the design.

Barry

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@144737 by Jeff DeMaagd

flavicon
face
----- Original Message -----
From: Barry Gershenfeld <EraseMEbarrySTOPspamspamRemoveMEZMICRO.COM>

> 2. I have always thought that the one place that X-10 "blew it"
> was that you cannot start a dimmer up from zero.  If the things
> would turn the lights on using a slow ramp up from "dim", I
> think the life of any bulb would be extended.  Maybe the bulb
> manufacturers "influenced" the design.

I don't think there's any need to suggest outside influences other than
pricing.  IMO X-10 simply plays it cheap, note the lack of 5 cent screws to
attach the serial dongle to the computer.  One is needed in order to use it
competently as a pass-through device, or jiggling the computer would cause
it to fall under the weight of the attached cable.

Jeff

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@152543 by Robert E. Griffith

flavicon
face
>> I don't think there's any need to suggest outside influences
>> other than pricing.  IMO X-10 simply plays it cheap,

That, and general ineptitude.  A few years ago a letter to the editor to
Home Automation magazine complained that most X10 products did not provide a
way to query the device as to its status.  Someone from X10 responded in a
letter to the editor (I think it may have been the founder/president)
something like "What we are doing is home control, not home feedback".  The
concept that feedback is an important part of control systems was apparently
foreign to him.

X10 is the poster boy for the worst what our patent system promotes.

OTOH, every once in a while, they do come up with an interesting,
inexpensive gadget.

--BobG


{Original Message removed}

2001\07\02@162024 by Michael C. Reid

flavicon
face
Regarding those small disc shaped devices, I understood that some brands
were diodes, dropping the voltage in half to save on bulb life, if you like
the idea of DC being introduced into the power grid of your home.

In the lighting control industry, we have information from Lutron that if
you decrease the voltage into a light bulb by 10% you double the life of the
bulb, 20%, quadruple the life, etc.

A big advantage of a control system is in the fading on of a load.  You do
not stress the filament with a 3 or 4 second fade time, like happens with a
mechanical switch, when the filament gets hit with the full voltage.  We
have clients who rarely replace light bulbs.

A word of warning for halogen light users, though.  In a normal incandcent
bulb, the tungsten filament slowly evaporates until it breaks.  The dark
spot on the bulb is the tungsten from the filament.  Halogen bulb need to be
run at full voltage about once a week for at least 10 minutes.  This process
redeposits the tungsten back onto the filament.  Doing this with halogen
bulbs increases their life expectancy considerably.

Also, if you ever decide to get into dimmable fluorescent lighting, it is
critical that the fluorescent bulbs or tubes be run 100 hours at full
intensity, without any dimming, before you start to dim them.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@162811 by Spehro Pefhany

picon face
At 03:22 PM 7/2/01 -0600, you wrote:
>Regarding those small disc shaped devices, I understood that some brands
>were diodes, dropping the voltage in half to save on bulb life, if you like
>the idea of DC being introduced into the power grid of your home.

It doesn't drop the voltage in half, it decreases it by about 30%.

Best regards,
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Spehro Pefhany --"it's the network..."            "The Journey is the reward"
spam_OUTspeffRemoveMEspamEraseMEinterlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
Contributions invited->The AVR-gcc FAQ is at: http://www.bluecollarlinux.com
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@183801 by Dale Botkin

flavicon
face
On Mon, 2 Jul 2001, Michael C. Reid wrote:

> Regarding those small disc shaped devices, I understood that some brands
> were diodes, dropping the voltage in half to save on bulb life, if you like
> the idea of DC being introduced into the power grid of your home.

Ummm...  no more than my bench power supply does.

Dale
--
A train stops at a train station.  A bus stops at a bus station.
On my desk I have a workstation...

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@184427 by Michael C. Reid

flavicon
face
your bench power supply has this thing called a transformer that isolates it
from the main power input!

{Original Message removed}

2001\07\02@185303 by Dale Botkin

flavicon
face
One does...  the other is a switcher.

On Mon, 2 Jul 2001, Michael C. Reid wrote:

> your bench power supply has this thing called a transformer that isolates it
> from the main power input!
>
> {Original Message removed}

2001\07\02@190341 by David VanHorn

flavicon
face
At 05:58 PM 7/2/01 -0500, Dale Botkin wrote:
>One does...  the other is a switcher.

Your switcher is either a flyback, providing it's own isolation, or
hideously dangerous.

Besides, what DC are we talking about here?
In reality, we're saying that the average current in one half cycle will be
higher than the other.
This is nothing new to the power company, they've dealt with a lot worse in
the past.

Your switchers will draw current on both cycles, BTW, as will your bench
supply, unless it's half wave rectified, which is a lousy design for a
bench supply.
--
Dave's Engineering Page: http://www.dvanhorn.org

I would have a link to http://www.findu.com/cgi-bin/find.cgi?KC6ETE-9 here
in my signature line, but due to the inability of sysadmins at TELOCITY to
differentiate a signature line from the text of an email, I am forbidden to
have it.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@190553 by michael brown

flavicon
face
> One does...  the other is a switcher.
>
> On Mon, 2 Jul 2001, Michael C. Reid wrote:
>
> > your bench power supply has this thing called a transformer that
isolates it
> > from the main power input!
> >

<SNIP>
>>>if you like the idea of DC being introduced into the power grid of your
home.
> >
> > Ummm...  no more than my bench power supply does.
> >
> > Dale

Seriously, could this "pulsed DC" load on the line really cause any ill
effects with other equipment?  I have never heard of this and am extremely
curious.  What about equipment that, say, contains a bridge rectifier for
example with no isolation transformer?  Wouldn't this be a "DC injector"
load on the line also?  Would there be a difference between full wave and
half wave rectifiers?  I am trying to imagine the flow of the DC current.
IOW, How does this work?

michael

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@190745 by Bob Ammerman

picon face
An 'off-line' switcher (like in a computer), which is driven directly off
the AC line will still have a higher frequency transformer in it, and will
almost always contain a full wave rectifier on the incoming A/C power. This
removes any DC component from the load the switcher presents to the house
mains.

Bob Ammerman
RAm Systems
(contract development of high performance, high function, low-level
software)

----- Original Message -----
From: "Dale Botkin" <TakeThisOuTdaleRemoveMEspam@spam@BOTKIN.ORG>
To: <EraseMEPICLISTRemoveMEspamMITVMA.MIT.EDU>
Sent: Monday, July 02, 2001 6:58 PM
Subject: Re: [EE]: Bulb Life (x:Modulating headlight)


> One does...  the other is a switcher.
>
> On Mon, 2 Jul 2001, Michael C. Reid wrote:
>
> > your bench power supply has this thing called a transformer that
isolates it
> > from the main power input!
> >
> > {Original Message removed}

2001\07\02@193904 by Michael C. Reid

flavicon
face
I rarely contribute to this forum but I love the winding road that comes out
of the various topics discussed.  Although an engineer by schooling I have
not been doing much engineering in my career.  As my skills get rusty it is
fun to read the stuff on this site.  As for the injected DC with a diode on
a light bulb, I just remember reading about it in an electronics magazine
one time.

It is interested to not how many products now days are using the reactance
of a capacitor to drop AC down and then rectify it.  Most motion sensor
lights use this circuit.  In school we were always taught that you always
had to use a transformer for isolation and safety.  I guess with the
pressure on price now this is not always to rule of thumb.  BTW, are there
any ramifications with a diode on the AC mains.  When you look at all the
other sources of dirt on the AC mains, is this really of importance?


An 'off-line' switcher (like in a computer), which is driven directly off
the AC line will still have a higher frequency transformer in it, and will
almost always contain a full wave rectifier on the incoming A/C power. This
removes any DC component from the load the switcher presents to the house
mains.

Bo
>

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@194523 by David VanHorn

flavicon
face
>
>Seriously, could this "pulsed DC" load on the line really cause any ill
>effects with other equipment?

Only in extreme cases, and I'm not sure you would notice.

>  I have never heard of this and am extremely
>curious.  What about equipment that, say, contains a bridge rectifier for
>example with no isolation transformer?

Draws current on both halves, that's what bridges are for!


>  Wouldn't this be a "DC injector" load on the line also?

No, it't just that it only draws current during one half-cycle.

>Would there be a difference between full wave and
>half wave rectifiers?

Yes, half wave draws current during half the wave.
Full wave draws current during the full wave..


>  I am trying to imagine the flow of the DC current.
>IOW, How does this work?

Pretty well, usually.
--
Dave's Engineering Page: http://www.dvanhorn.org

I would have a link to http://www.findu.com/cgi-bin/find.cgi?KC6ETE-9 here
in my signature line, but due to the inability of sysadmins at TELOCITY to
differentiate a signature line from the text of an email, I am forbidden to
have it.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@200408 by michael brown

flavicon
face
> >
> >Seriously, could this "pulsed DC" load on the line really cause any ill
> >effects with other equipment?
>
> Only in extreme cases, and I'm not sure you would notice.
>
> >  I have never heard of this and am extremely
> >curious.  What about equipment that, say, contains a bridge rectifier for
> >example with no isolation transformer?
>
> Draws current on both halves, that's what bridges are for!

I know that, but I 'ass-u-me'd that a full wave rectifier was used just
because it gave a smother dc supply, that was easier to filter, not that it
was there to present a "balanced" load to the line.  Plus it makes more
"power" available at a higher voltage.

{Quote hidden}

Not exactly what I was looking for there.

>
>
> >  I am trying to imagine the flow of the DC current.
> >IOW, How does this work?
>
> Pretty well, usually.

OK.  I am trying to imagine the flow of the DC current within the big
picture involving the "offending" light bulb, a neutral and a hot wire.
What "unwanted" effect on the AC mains is obtained from the diode inline
with the bulb?  I hope I have been specific enough here.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@201436 by Alexandre Domingos F. Souza

flavicon
face
>your bench power supply has this thing called a transformer that isolates it
>from the main power input!

       Maybe a switcher one?


---8<---Corte aqui---8<----

Alexandre Souza
spamtaito.....spamspamterra.com.br
http://planeta.terra.com.br/lazer/pinball/

---8<---Corte aqui---8<----

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@201656 by David VanHorn

flavicon
face
At 07:01 PM 7/2/01 -0500, michael brown wrote:
> > >
> > >Seriously, could this "pulsed DC" load on the line really cause any ill
> > >effects with other equipment?
> >
> > Only in extreme cases, and I'm not sure you would notice.
> >
> > >  I have never heard of this and am extremely
> > >curious.  What about equipment that, say, contains a bridge rectifier for
> > >example with no isolation transformer?
> >
> > Draws current on both halves, that's what bridges are for!
>
>I know that, but I 'ass-u-me'd that a full wave rectifier was used just
>because it gave a smother dc supply, that was easier to filter, not that it
>was there to present a "balanced" load to the line.  Plus it makes more
>"power" available at a higher voltage.

Full wave is relevant to a center tapped transformer, and only uses half
the windings at a time.
Bridge works without the center tap, and uses all the windings all the time.
In a bridge, you dissipate for two diode drops in series, in a full wave,
only one.
Otherwise they are the same.



> > >Would there be a difference between full wave and
> > >half wave rectifiers?
> >
> > Yes, half wave draws current during half the wave.
> > Full wave draws current during the full wave..
>
>Not exactly what I was looking for there.

That is the only difference that I'm aware of.


>OK.  I am trying to imagine the flow of the DC current within the big
>picture involving the "offending" light bulb, a neutral and a hot wire.
>What "unwanted" effect on the AC mains is obtained from the diode inline
>with the bulb?  I hope I have been specific enough here.

None.. The pole transformer sees more load on one half of the cycle than
the other.
If EVERYBODY used diodes on EVERYTHING, and they were ALL installed the
same way, it would likely be a problem.  Odds of happening, near zero.


--
Dave's Engineering Page: http://www.dvanhorn.org

I would have a link to http://www.findu.com/cgi-bin/find.cgi?KC6ETE-9 here
in my signature line, but due to the inability of sysadmins at TELOCITY to
differentiate a signature line from the text of an email, I am forbidden to
have it.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@201854 by David VanHorn

flavicon
face
Sorry, correction:

Odds of happening:  1 - (the sum of the infinite series, 0.9999....)

(ducks, and runs for cover)
--
Dave's Engineering Page: http://www.dvanhorn.org

I would have a link to http://www.findu.com/cgi-bin/find.cgi?KC6ETE-9 here
in my signature line, but due to the inability of sysadmins at TELOCITY to
differentiate a signature line from the text of an email, I am forbidden to
have it.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@210635 by michael brown

flavicon
face
> >OK.  I am trying to imagine the flow of the DC current within the big
> >picture involving the "offending" light bulb, a neutral and a hot wire.
> >What "unwanted" effect on the AC mains is obtained from the diode inline
> >with the bulb?  I hope I have been specific enough here.
>
> None.. The pole transformer sees more load on one half of the cycle than
> the other.
> If EVERYBODY used diodes on EVERYTHING, and they were ALL installed the
> same way, it would likely be a problem.  Odds of happening, near zero.

Ok, I understand.  But originally, there was talk of a DC component being
placed onto the line because of the diode.  Would the effect of the
diode/bulb be comparable to an impedance mismatch in feed lines along with
the associated consequences?

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\02@213612 by David VanHorn

flavicon
face
>
>Ok, I understand.  But originally, there was talk of a DC component being
>placed onto the line because of the diode.  Would the effect of the
>diode/bulb be comparable to an impedance mismatch in feed lines along with
>the associated consequences?

I don't think so.

I don't know where this DC component came from. It's a simple circuit, on
the secondary of a transformer.
Remove the primary current, and you'll find no DC remainder.
The only effect that I can see, is more current in one half or the other of
the cycle.
Given that each individual load is small, and the fact that any large
number of them will average twoard a 50/50 distribution of polarity, I
don't see any problems.

This sounds like the sort of troubles you get into when you chrome-plate
your roll center.

--
Dave's Engineering Page: http://www.dvanhorn.org

I would have a link to http://www.findu.com/cgi-bin/find.cgi?KC6ETE-9 here
in my signature line, but due to the inability of sysadmins at TELOCITY to
differentiate a signature line from the text of an email, I am forbidden to
have it.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\07\03@075941 by Olin Lathrop

face picon face
> > Regarding those small disc shaped devices, I understood that some brands
> > were diodes, dropping the voltage in half to save on bulb life, if you
like
> > the idea of DC being introduced into the power grid of your home.
>
> Ummm...  no more than my bench power supply does.

A bench power supply would have a full wave bridge, which draws current on
both halves of the AC cycle.  A single series diode only conducts for one of
the halves, thereby drawing an average DC current.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olinspam_OUTspam@spam@embedinc.com, http://www.embedinc.com

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2001\07\03@075953 by Olin Lathrop

face picon face
> your bench power supply has this thing called a transformer that isolates
it
> from the main power input!

Unless its a "plain old" linear supply, it more likely full wave rectifies
the AC to make DC, then chops it thru a transformer at much higher than
60Hz.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, .....olinspamspam.....embedinc.com, http://www.embedinc.com

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2001\07\03@075958 by Olin Lathrop

face picon face
> What about equipment that, say, contains a bridge rectifier for
> example with no isolation transformer?  Wouldn't this be a "DC injector"
> load on the line also?

No.

> Would there be a difference between full wave and
> half wave rectifiers?

Yes.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olinKILLspamspamEraseMEembedinc.com, http://www.embedinc.com

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2001\07\03@084224 by Dale Botkin

flavicon
face
On Mon, 2 Jul 2001, David VanHorn wrote:

> At 05:58 PM 7/2/01 -0500, Dale Botkin wrote:
> >One does...  the other is a switcher.
>
> Your switcher is either a flyback, providing it's own isolation, or
> hideously dangerous.

Yes, but the rectifcation is done before the isolation, which is what the
original poster was complaining about -- recifying AC directly.

> Besides, what DC are we talking about here?
> In reality, we're saying that the average current in one half cycle will be
> higher than the other.
> This is nothing new to the power company, they've dealt with a lot worse in
> the past.

Yes, that was my point.

> Your switchers will draw current on both cycles, BTW, as will your bench
> supply, unless it's half wave rectified, which is a lousy design for a
> bench supply.

I know.  They're both excellent power supplies, actually.

Dale
--
A train stops at a train station.  A bus stops at a bus station.
On my desk I have a workstation...

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


'[OT]: Priority Green was Modulating a headlight'
2001\07\03@095632 by Douglas Butler

flavicon
face
In Tokyo I saw the ultimate speed trap.  On a city street (aprox 25 MPH
limit) at the side of the curb was a camera tripod with a combo speed
gun/video camera.  There was a shopping bag set in front of the camera
so it could not be seen by oncoming traffic.  A small cable lead around
the corner of the building where there was a folding desk, two seated
cops with a video monitor and recording equipment.  There was a third
cop in an orange suit with a huge orange flag, and TWO motorcycle cops.
It was invisible to the oncoming traffic, with a total of five cops and
nary a donut in sight!

If only we took speed limits as seriously in the USA...

Sherpa Doug

> {Original Message removed}

2001\07\03@105539 by Roman Black

flavicon
face
Douglas Butler wrote:
>
> In Tokyo I saw the ultimate speed trap.  On a city street (aprox 25 MPH
> limit) at the side of the curb was a camera tripod with a combo speed
> gun/video camera.  There was a shopping bag set in front of the camera
> so it could not be seen by oncoming traffic.  A small cable lead around
> the corner of the building where there was a folding desk, two seated
> cops with a video monitor and recording equipment.  There was a third
> cop in an orange suit with a huge orange flag, and TWO motorcycle cops.
> It was invisible to the oncoming traffic, with a total of five cops and
> nary a donut in sight!
>
> If only we took speed limits as seriously in the USA...


Now just imagine the benefits to society if all
those cops and dollars were utilised to prevent
crime! Such a shame dollar raising comes first and
crime fighting comes a very poor second. :o(
-Roman

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2001\07\03@115714 by D Lloyd

flavicon
face
part 1 2370 bytes content-type:text/plain; charset=us-ascii
Hi,

It appears that the Japanese have a different (or did do last time I heard
about it) philosophy to Westerners. In Japan, it seems people are employed
to do things that would not be considered here.

For example, if someone puts up some scaffolding around a building, they
don't just put signs up to warn people....they have guys employed to
physically ward you away from the danger etc.

Yes, it does seem that the police are interested in catching offenders for
offences that have a monetary value attached to them. Still, speeding is an
offence that kills/maims/causes distress for a *significant* number of
innocent people each year...

Maybe they should start confiscating vehicle for each offence.....and you
get it confiscated longer the more times you get caught....that might hurt
more. (I have a vested interest in this with being a cyclist!)

Dan




(Embedded     Roman Black <EraseMEfastvid@spam@spam@spam@EZY.NET.AU>@spam@spam@spam@MITVMA.MIT.EDU>> image moved   03/07/2001 15:56
to file:
pic02600.pcx)





Please respond to pic microcontroller discussion list
     <
@spam@PICLISTspamspamKILLspamMITVMA.MIT.EDU>
Sent by:  pic microcontroller discussion list <spamBeGonePICLISTRemoveMEspamEraseMEMITVMA.MIT.EDU>


To:   RemoveMEPICLISTKILLspamspamRemoveMEMITVMA.MIT.EDU
cc:
Subject:  Re: [OT]: Priority Green was Modulating a headlight

Security Level:?         Internal


Douglas Butler wrote:
{Quote hidden}

Now just imagine the benefits to society if all
those cops and dollars were utilised to prevent
crime! Such a shame dollar raising comes first and
crime fighting comes a very poor second. :o(
-Roman

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.






part 2 165 bytes content-type:application/octet-stream; (decode)

part 3 131 bytes
--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2001\07\03@120932 by Dale Botkin

flavicon
face
On Wed, 4 Jul 2001, Roman Black wrote:

{Quote hidden}

Actually, I was just thinking about that this morning as we drove through
town.  Since I was a passenger I got to do more close observation of those
around me.  Drivers with headphones on (quite illegal, for obvious
reasons), unsafe vehicles, vehicles missing lights, you name it.  I think
my state dropping its vehicle inspection requirements was a mistake.

But I also started thinking about the number of cops busy with traffic
enforcement.  I think there may be a benefit to increasing it if you take
a long-term view.  I think we've raised a generation or two of people who
don't take police seriously because, from the time they were little tiny
miscreants, they saw their Mom & Dad & sitsers/brothers/neighbors getting
away with routinely, casually breaking the law.  Red light?  No cop, no
stop.  Yellow light?  Speed up.  Speed limit?  Ignore it.  It's only the
law, after all, and laws can obviously be ignored if they're inconvenient
or we don't like them for some other reason.

I think perhaps the reduction in and trivialization of traffic enforcement
has been the camel's nose under the tent, and now we're being pushed out
of the tent because so many people were exposed to this casual disregard
for the law.  After all, if traffic laws mean nothing, why would drug laws
be taken any more seriously?  Pretty soon you can rationalize disregarding
any law that's not convenient to you personally.

Anyway, just a random thought on this fine second official day of my
vacation.

Dale
--
A train stops at a train station.  A bus stops at a bus station.
On my desk I have a workstation...

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


'[EE]: Bulb Life (x:Modulating headlight)'
2001\07\03@133227 by Douglas Butler

flavicon
face
Note that your house is fed by a transformer from the utility.  That
transformer won't allow any DC to accumulate on the power lines.  You
may provide an asymetrical load to the generator, but other appliances
in you house in parallel with the rectified ligh bulb will not know the
difference.  In theory you electric meter could detect the difference,
but I doubt it cares.

Sherpa Doug

> {Original Message removed}

'[OT]: Priority Green was Modulating a headlight'
2001\07\03@211539 by Alexandre Domingos F. Souza

flavicon
face
>Now just imagine the benefits to society if all
>those cops and dollars were utilised to prevent
>crime! Such a shame dollar raising comes first and
>crime fighting comes a very poor second. :o(

       Are you living in Brazil, Roman? :o)


---8<---Corte aqui---8<----

Alexandre Souza
TakeThisOuTtaitospamterra.com.br
http://planeta.terra.com.br/lazer/pinball/

---8<---Corte aqui---8<----

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2001\07\04@052922 by Roman Black

flavicon
face
Alexandre Domingos F. Souza wrote:
>
> >Now just imagine the benefits to society if all
> >those cops and dollars were utilised to prevent
> >crime! Such a shame dollar raising comes first and
> >crime fighting comes a very poor second. :o(
>
>         Are you living in Brazil, Roman? :o)


Not yet! :o)
-Roman

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email spamBeGonelistservKILLspamspamTakeThisOuTmitvma.mit.edu with SET PICList DIGEST in the body


'[EE]: Bulb Life (x:Modulating headlight)'
2001\07\04@140755 by Peter L. Peres

picon face
> dc in mains: ill effects

Let me put this in perspective: If you have one nightlight running
continuously at 20W and put a diode in series with it, nothing will
happen.

If your 4kW electric heater has a burned out thermostat and you wisely
decide to wire a 20A diode across the dead thermostat so you can have it
run at 2.2kW overnight, then you may or may not cause a utility
transformer on a pole outside your house to catch fire after a long enough
time (and assuming some higher load cooperation from other loads, like the
washing machine, a fridge or two and a couple more heaters). If the
electricity company catches you doing this you might be the guy paying for
all the burned out utility transformers in the past centuries.

The technical explanation has to do with transformer saturation which can
cause overheating followed by thermal runaway or a parted wire or
insulation -> flash, boom.

Peter

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email EraseMElistserv.....spamKILLspammitvma.mit.edu with SET PICList DIGEST in the body


'[EE]: LED bicycle headlight'
2001\07\08@004532 by Roman Black

flavicon
face
Patrik Husfloen wrote:
>
> Neat, I was looking to do the same thing, though I have a dynamo/generator driving my bulbs.
> so I guess I'd need some rectifier circuit, using a backup cap to give som glow while stopped might be nice also.
> too bad I have no clue on electronics :)


Hi Patrik, what about a small NiCd or NiMH
battery pack (like the free ones someone gave
to piclisters before?) Small and lightweight.

That gives continued glow when the bicycle is
stopped, steadier glow when moving and is a very
simple way of protecting the LED headlight from
overvoltage.

You need the NiCd battery, LED and it's resistor,
and maybe a protect zener and on/off switch
would round it out nicely. Nothing too complicated
there.:o)
-Roman

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


2001\07\09@111324 by Patrik Husfloen

picon face
It seems from the Bulb life thread that there are a lot of drivers ICs for white LEDs
is that for any special reason? I mean your regular red LED never had a driver IC..
are the white LEDs "special" in some way, or can I drive them with a series resistor like I do with all the other LEDs?

I'm not sure how many LEDs one would need to give sufficient lite..I was thinking 4 maybe..and a couple of red ones for the tail light..
you mentioned NiCd, I thought those could only be recharged when they were completly drained or you pretty much ruined them.

I wasn't part of the Piclist at the time for thsoe free cells :/

/Patrik
{Original Message removed}

2001\07\09@121706 by Bob Ammerman

picon face
The white LEDs have a rather high forward voltage (3.6V ?) so to drive them
off one or two batteries you typically need some sort of DC-DC converter.
Also by using current instead of voltage feedback, the converter can be
quite efficient.

Bob Ammerman
RAm Systems
(contract development of high performance, high function, low-level
software)

{Original Message removed}

2001\07\09@123005 by Patrik Husfloen

picon face
ok, I see,
I wonder if that zentrix or something in that direction offers samples :)
will have to look into that..
would be pretty cool to fit LEDs on the bike for light.
I guess I iwll add it to my giant TODO list..
right after building a new computer case :)

Cheers,
Patrik

{Original Message removed}

2001\07\09@160705 by mike

flavicon
face
I think this is for current regulation - to maximise battery life, and
get a consistent tint - the colour of white LEDs varies with current
as the phosphor characteristic is nonlinear, giving a different
balance between the blue LED colour and the yellow phosphor colour.
You can drive them with resistors in most applications, as slight
colour changes are not often too important.  
On Mon, 9 Jul 2001 17:14:46 +0200, you wrote:

{Quote hidden}

>{Original Message removed}

2001\07\09@172911 by Jinx

face picon face
> are the white LEDs "special" in some way, or can I drive
> them with a series resistor like I do with all the other LEDs?

A 330 ohm resistor with a 6V gel cell is fine

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email spamlistservspammitvma.mit.edu with SET PICList DIGEST in the body


2001\07\09@202450 by Patrik Husfloen

picon face
What is a gel cell, and I can I charge it with a dynamo from a bike?

----- Original Message ----- From: "Jinx" <joecolquittSTOPspamspamCLEAR.NET.NZ>
To: <PICLISTSTOPspamspamKILLspamMITVMA.MIT.EDU>
Sent: Monday, July 09, 2001 11:28 PM
Subject: Re: [EE]: LED bicycle headlight


> > are the white LEDs "special" in some way, or can I drive
> > them with a series resistor like I do with all the other LEDs?
>
> A 330 ohm resistor with a 6V gel cell is fine
>
> --
> http://www.piclist.com#nomail Going offline? Don't AutoReply us!
> email @spam@listserv.....spamspammitvma.mit.edu with SET PICList DIGEST in the body
>
>
--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email spamlistserv.....spam.....mitvma.mit.edu with SET PICList DIGEST in the body


2001\07\10@012150 by Jinx

face picon face
Patrik, further to my last reply, I made this up while watching the
midday news today. I baulked at paying $30 for a lamp I didn't
really like. Used scrap and got exactly what I wanted

http://home.clear.net.nz/pages/joecolquitt/makelamp.html

I've stuck with the plain resistor as the gel cell is rechargeable
and the lamp is used intermittently, but I would consider a driver
chip if either I was running disposables or using the light for long
periods

--
http://www.piclist.com hint: To leave the PICList
piclist-unsubscribe-request.....spammitvma.mit.edu


2001\07\10@012205 by Jinx

face picon face
> What is a gel cell, and I can I charge it with a dynamo from a bike?

A sealed lead battery. The 6V 3Ah I buy is around NZ$22 (US$9).
One thing you need to keep a careful eye on is charging voltage
and limiting the discharge voltage. Go below a certain voltage and
not charge it PDQ and you'll permanently stuff it. Maxim will have
details about battery mangement ICs, which I'd recommend for
getting the best lifetime. I have a smart charger for gel cells so
haven't needed to look into it and can't supply details, sorry. As
for using the dynamo, I've never measured the output of one but
I guess it must be a few volts. If it isn't enough to directly charge
a battery you may need to build a voltage doubler and then regulate
it. It's all sounding very complicated but it isn't really. The money
you'll save over disposable batteries and the piece of mind gained
from having a second source of power will be worth it

--
http://www.piclist.com hint: To leave the PICList
KILLspampiclist-unsubscribe-requestspam_OUTspammitvma.mit.edu


2001\07\10@105647 by Patrik Husfloen

picon face
Well currently I use a dynamo (this is a very old bike, 20-30 years or so) and it has filametn bulbs front and rear, what I would like is a constanst light output no matter how fast I bike, which is not the case atm, and light when the bike isn't moving, in case you have to stop for traffic or something.
One idea would be to have the light on for about a minute after the dynamo stops charging.

I was browsing maxim earlier for those battery ICs, found a few, most were programmable by an SMB bus, I'd rather keep this as simple as possible.

Thanks for the info though,

Patrik
{Original Message removed}

2001\07\10@172116 by Jinx

face picon face
> Well currently I use a dynamo (this is a very old bike, 20-30 years
> or so) and it has filametn bulbs front and rear, what I would like is
> a constanst light output no matter how fast I bike, which is not the
> case atm, and light when the bike isn't moving, in case you have
> to stop for traffic or something. One idea would be to have the
> light on for about a minute after the dynamo stops charging.

> I was browsing maxim earlier for those battery ICs, found a few,
> most were programmable by an SMB bus, I'd rather keep this
> as simple as possible

Patrik, the first decision you need to make is whether you stick
with filaments or change to LEDs. That will then help you decide
what back-up supply to use. If you stay with filaments, a supercap
won't do it (two bulbs could use 1500mA). Go to LEDs and you'll
find the current requirements drop dramatically to 20-30mA, which
could be supplied by a battery or supercap. I think this is really a
case of putting aside a Saturday and as Nike would say, just do
it ;-)   BTW, are you using a hub or friction dynamo ?

--
http://www.piclist.com hint: To leave the PICList
spam_OUTpiclist-unsubscribe-requestspamTakeThisOuTmitvma.mit.edu


2001\07\10@182129 by Patrik Husfloen

picon face
Well I am going to replace bulbs with LED that's already decided.
I don't have the parts to just _do it_ though, I would need to figure out what I need and order it.
I checked white LEDs today, they are about $2-3 (USD) each.
I figure using 3-4 would give enough light to be legal.
I was thinking a supercap would be easier to use, I also read the pulsing the light would be more efficient, in that case just a resistor isn't going to do it..

About the dynamo, not sure really, it's one of those that "leans" on the tire for rotation.
I'm guessing that is friction, this hub thing, what is that?

Any suggestions would be greatly appriciated,

Patrik

{Original Message removed}

2001\07\10@201312 by David P. Harris

picon face
Can you tell me who sells teh super caps?
Thanks, David


Patrik Husfloen wrote:

{Quote hidden}

> {Original Message removed}

2001\07\10@211703 by Patrik Husfloen

picon face
I havn't looked yet but I was planning on buying them from Elfa (.se).
If I decide to use them that is.

Patrik
{Original Message removed}

2001\07\10@220817 by Jinx

face picon face
> Well I am going to replace bulbs with LED that's already decided

That's good. Now, if you want to use the dynamo as the charger
(although honestly I think you'd be better off going to battery power
with a separate charger. After all, you won't be needing all those
amps anymore) then you'll have to do some measurements on it.
I expect it will be AC, so some circuit like that I posted the other
day will do you for rectifying the AC to DC for charging the battery.
The diodes can be 1N4001's or a pre-packaged bridge, the
smallest one on the shelf will suffice. Once you have a DC voltage
to measure, then you can think about what needs to be done with
it to charge the battery properly. If it's a supercap, then you'll need
to limit the voltage, probably with a low dropout 5V regulator.

> I also read the pulsing the light would be more efficient, in that
> case just a resistor isn't going to do it

What I think you mean is that you could pulse the LED with more
energy to make it brighter, but still keep the average power at a
safe level, the same way that IR LEDs are pulsed with high current
to get extra range. However, an IR receiver is not the same as a
human eye, and I couldn't say for sure whether high current pulsing
would necessarily mean a greater perceived brightness. Perhaps
it would be better to start off simply with a dropping resistor and
DC. You may find that's perfectly acceptable. I know I'm OK with
my LEDs

> About the dynamo, not sure really, it's one of those that "leans"
> on the tire for rotation.

Yuck. Haven't used one of those for a long long time. Complete
PITA as I remember. I spend enough time in 1st already on
Auckland's damn hills (for those who don't know, Auckland is
built on around 20 volcanic cones, errr, extinct ones hopefully,
up and down, up and down,........)

> I'm guessing that is friction, this hub thing, what is that?

It's built into the rear axle. If you plan to stick with a dynamo as the
primary supply and you no longer want the extra effort of the tyre
dynamo, maybe you could look for a back wheel with a hub one

--
http://www.piclist.com hint: To leave the PICList
.....piclist-unsubscribe-request.....spamRemoveMEmitvma.mit.edu


2001\07\11@004242 by Roman Black

flavicon
face
Patrik Husfloen wrote:
>
> Well I am going to replace bulbs with LED that's already decided.
> I don't have the parts to just _do it_ though, I would need to figure out what I need and order it.
> I checked white LEDs today, they are about $2-3 (USD) each.
> I figure using 3-4 would give enough light to be legal.

Check that they are the 6000mCd ones. You can
also get 1600mCd and 4000mCd which are not as good.


> I was thinking a supercap would be easier to use, I also read the pulsing the light would be more efficient, in that case just a resistor isn't going to do it..

Efficiency is not a problem, these leds are MUCH
more efficient than thefilament bulbs you have now.
I've used a 3.3F supercap to drive a led, soon
went back to a few small NiCds. Much better capacity
and flatter discharge curve than the supercap.
:o)
-Roman

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\11@004845 by Roman Black

flavicon
face
David P. Harris wrote:
>
> Can you tell me who sells the super caps?
> Thanks, David

They have been discontinued from most manufacturers
due to problems with corrosive leakage and failures,
and the high price of course.
We have lots of manufacturer mod notes saying to
replace the supercaps with button NiCds or Lithium
cells. Supercaps are not as good as the concept
suggests, very corrosive electrolyte and fussy
construction to get the capacity, which still does
not compare with NiCd for expected life or
capacity.
-Roman


> Patrik Husfloen wrote:
>
> > Well I am going to replace bulbs with LED that's already decided.
> > I don't have the parts to just _do it_ though, I would need to figure out what I need and order it.
> > I checked white LEDs today, they are about $2-3 (USD) each.
> > I figure using 3-4 would give enough light to be legal.
> > I was thinking a supercap would be easier to use,

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\11@014632 by Russell McMahon

picon face
> > About the dynamo, not sure really, it's one of those that "leans"
> > on the tire for rotation.

It MUST go - almosty all the energy going into it is lost to mechanical
loss. You will not feel the power taken by a LD lamp if efficiently done.
Try a magnet or a few magnets evenly spaced on the rim and a pickup coil.
You may be pleasantly surprised. This is already done by others.

> Yuck. Haven't used one of those for a long long time. Complete
> PITA as I remember. I spend enough time in 1st already on
> Auckland's damn hills (for those who don't know, Auckland is
> built on around 20 volcanic cones, errr, extinct ones hopefully,

AFAIK there are actually about 100 distinct volcanic cones on the Auckland
field - many are no longer easily distinguishable as such. This is a
hot-spot in the volcanic plate much as that which forms the Hawaiian
Islands - just not so impressive. The field is still live but all past
mounds are dead. The last volcano was about 800 years ago (Rangitoto Island
just off the Auckland City coast). Rangitoto accounts for twice as much
material as all the rest of the volcanos before it combined !!! If we get
another of similar size in the city area proper much of Auckland will cease
to exist.

The good news is that Auckland volcanoes are getting more frequent and
larger with time. The average time between is about 2000 years and recently
its rather shorter. That means we are overdue (honestly) for another one and
it should be a real beaut. With any luck Jinx and I should see another one
here in out lifetimes. The main difference is that he lives on the edge of
the volcano zone and I live comfortably outside it - would do wonders for my
property price :-)

If you want REAL volcanoes a little South from here there is a volcano so
large that the locals don't know it is there !!! Largest volcanic eruption
on earth in the last 20,000 years plus. Closest thing to Olympus Mons that
you are liable to be able to touch in this lifetime. So big that we call it
"the volcanic plateau" - its real name SHOULD be Mount Taupo. Crater is a
lake 25 miles wide and about 40 miles long. Ten miles or so south there is a
5000 foot mountain (Tongariro/Ngaruahoe - one mountain but we think it is
two)) . In the last eruption the ash wave from Taupo overtopped this
mountain by about 3000 feet. You can run but you can't hide. The eruption
would have been observable throughout the world (if you had been there).

.

           Russell

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\11@171128 by David P. Harris

picon face
OK- I get the picture --- stick with the batteries -- Thanks :-)
David

Roman Black wrote:

{Quote hidden}

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\07\12@140644 by Peter L. Peres

picon face
> corrosive supercaps

That's new to me Roman. Most supercaps have a solid dielectric. Can you
quote a make that does not ? The main failure mode is by increased leakage
afaik. This is 'helped' by the long (100ft or more) length of very thin
(10 microns) tape dielectric in them. The slightest material fault causes
leakage or breakdown (at ridiculously low voltages - like 1.5V). Afaik
they don't age electrically, only material breakdown does them in.

Peter

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics



'[EE]: Modulating a headlight'
2001\09\02@201431 by Spehro Pefhany
picon face
At 03:27 PM 6/28/01 -0700, you wrote:

>Is a P-Channel Mosfet difficult to drive from a TTL logic level, such as a
>PIC.

It will be "off" when the gate voltage is at 12V (13.8V), so you can drive it
easily with an open-collector driver (eg. 2N4401) with a base resistor and a
pullup resistor. You may want to use a zener from source to gate and an
additional
series resistor to prevent punchthrough of the gate oxide on spikes in the
supply voltage.

Best regards,

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Spehro Pefhany --"it's the network..."            "The Journey is the reward"
spam_OUTspeffTakeThisOuTspamEraseMEinterlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
Contributions invited->The AVR-gcc FAQ is at: http://www.bluecollarlinux.com
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email EraseMElistservspamBeGonespamKILLspammitvma.mit.edu with SET PICList DIGEST in the body


2001\09\02@233636 by Gennette, Bruce

flavicon
face
Sorry to put a dampener on you all but technology is a-changin'

The 'next generation' of headlamps (already available on some models) are
short arc lamps in tiny tubes operating at 36 volts or so.  They have
drivers in their bases to create the startup and run voltages/currents from
12V.  They even compensate for 'aging' by adjusting the inputs over time.

They *DO NOT* like to be restarted hot nor ramped up and down.

The 'next generation' of vehicles are going to operate with 36 volt
batteries (alright 42 volts fully charged) to keep the size of voltage
losses, cables and electric motors down.  Many 12V appliances will still be
used on a legacy 12V circuit that will be avaliable, but a lot of devices
will be changing over to 36V (headlamps certainly).

So be prepared.  Do your homework; it may be worthwhile developing a device
for older style headlamps (after all there are a lot of them), but it also
may not be worth it.

Bye.

{Original Message removed}


'[PIC] : car headlight control'
2004\01\03@220854 by reinaldo
flavicon
face
HELP, i'm working on a "simple" headlight, it's suposed to
adjust the headlight with reference to a resistor pot inside
the car. i'm using AD conversion to work out the position.
my list of problems:
=the pot fitted to the headlight makes (say) only a
30°turn, in the car the pot turns about 200°, to scale
this down i'm using a division routine to work out a ratio.
=this will need for the unit to be calibrated
=i need to store the calibration values in eeprom
=i then need to apply the ratio to the pot in the
dashboard.

my concern is the code is getting too big and complicated
for such a simple device, and maybe too slow?
is there an easier way?
thanks

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics

'[PIC]: car headlight control'
2004\01\03@221931 by John J. McDonough

flavicon
face
Sounds like it to me

I assume you are using a D/A to move the pot in the headlight? (seems
strange).  Anyway, you want to make the high end of the dashboard pot set to
the maximum voltage of your A/D.  Now, presuming you are using one of the
PIC 10 bit A/D, and lets just assume, for the sake of argument, your D/A is
an 8 bit D/A, just shift the dashboard pot position right 2 bits before
sending it you to the D/A.

If you are using a stepper motor in the headlight pot, then figure out the
number of steps, and do a little dancing around with the dashboard pot
voltage to make the stepper count work out.  Watch out for your A/D
resolution, though.

I am really agin complicated, but I doubt you have to worry about slow.
Physical things like a pot are amazingly slow compared to the PIC.

72/73 de WB8RCR    http://www.qsl.net/wb8rcr
didileydadidah     QRP-L #1446 Code Warriors #35

----- Original Message -----
Sent: Saturday, January 03, 2004 9:58 PM
Subject: [PIC] : car headlight control


my concern is the code is getting too big and complicated
for such a simple device, and maybe too slow?
is there an easier way?
thanks

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics

2004\01\03@232651 by reinaldo

flavicon
face
sorry i was very vague
the headlight motor is a simple DC motor, and i'm going to
fit a resitor pot to the headlight to measure the angle of
the headlight, say this pot gives me 80 when the light is
down and 200 when fully open, the pot in the dash will give
0 to 255 ofcourse. so i'll need 0 to equal 80, 200 to equal
255, AND every 2.125 steps of the dash pot correspond to 1
step of the headlight pot. i can't measure .125 from a pot.
but, i'll measure the dash pot(say 60) divided 2.125 =
28.23.. so that's 28 steps for the headlight pot + the
bottom position(80) = 108, so now i work out wich way to
turn the motor untill i reach 108. that way i hope to use
the full range of the dash pot.
now you can see i need division routines, i need to store
top and bottom levels while the power is off, and i also
need to constantly calculate what position the dash pot
works out to be for the headlight pot. i don't dare remove
the current motor and replace it for a stepper, also
remember everything needs to be done for both headlights :(
can you think of a simpler method?
thanks for your advice

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics

'[PIC] : car headlight control'
2004\01\04@000645 by Ken Pergola

flavicon
face
Hi Reinaldo,

Are you trying to accomplish what Preston Tucker did with the center
headlight on his automobiles - have it move in relation to the steering
wheel?

Other than that reason, it's not too clear to me from your post why you need
move the headlights? Just trying to get more info. Sounds like a neat
project.

Best regards,

Ken Pergola

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

2004\01\04@001707 by reinaldo

flavicon
face
hmm, i haven't heard of Preston Tucker
maybe it's not too different, but i'll just have a pot to
adjust how far the pop-up headlights will open/close, but it
won't be connected to the sterring wheel.
actaully i'm not too sure myself what the porpuse of this
is, as a buddy asked me to do this for him, i said sure
sounds easy! :(

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

'[PIC]: car headlight control'
2004\01\04@004026 by David Duffy

flavicon
face
reinaldo@IHUG.CO.NZ wrote:

>sorry i was very vague
>the headlight motor is a simple DC motor, and i'm going to
>fit a resitor pot to the headlight to measure the angle of
>the headlight, say this pot gives me 80 when the light is
>down and 200 when fully open, the pot in the dash will give
>0 to 255 ofcourse.
>

Just add resistors in series to the top and bottom of the dash pot.
This will give you your reduced range when the A-D reads it.
Either fixed resistors or preset pots will do the trick. Simple.
David...

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

'[PIC] : car headlight control'
2004\01\04@004235 by Ken Pergola

flavicon
face
Hi Reinaldo,

I apologize for not reading your post carefully enough to see you are
dealing with pop-up headlights. I would check with your buddy on the "why"
of this project -- knowing this could totally change your approach to this
project, and possibly make your job a lot easier. You never know, he might
want to use this headlight capability for hunting night crawlers or
something. There could be a thousand reasons why he would want to do this to
his headlights.

Regards,

Ken Pergola

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

'[PIC]: car headlight control'
2004\01\04@004443 by reinaldo

flavicon
face
ha!!
so simple! i got too involved in software to consider the
hardware

thanks

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

2004\01\04@010553 by Picdude

flavicon
face
Which PIC are you using?  Most that I've worked with have a 10-bit A/D, so you'd actually get a range of 0-1023, and instead of 2.125, your steps would be 8.5.

I actually prefer to do the math and reduce the number of components, but if you need more resolution from the A/D, then how about using a 3-resistor voltage divider with the 2 center points going to VREF+ and VREF- of the A/D converter.  Something like this ...

     +V
      ^
      |
     [R1]
      |
      o----> To Vref+
      |
     [R2]
      |
      o----> To Vref-
      |
     [R3]
      |
      v
     GND

In this case, the A/D will read "0" when the sampled voltage is equal to V*(R1+R2)/R3 and 255 (or 1023 if using a 10-bit A/D) when the sampled voltage is equal to V*R1/(R2+R3).  Remember that there is a minimum difference allowed between Vref+ and Vref- (~2V for some of the 16F-series chips IIRC) -- see the datasheet for the official spec.

Cheers,
-Neil.


On Saturday 03 January 2004 10:25 pm, RemoveMEreinaldospamBeGonespamspamIHUG.CO.NZ scribbled:
{Quote hidden}

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

'[PIC] : car headlight control'
2004\01\04@010801 by Picdude

flavicon
face
On Saturday 03 January 2004 11:15 pm, @spam@reinaldospamspamIHUG.CO.NZ scribbled:
> hmm, i haven't heard of Preston Tucker

Check out the movie called "Tucker".

Cheers,
-Neil.

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

'[OT] : car headlight control'
2004\01\04@013330 by Jinx

face picon face
> Are you trying to accomplish what Preston Tucker did with the
> center headlight on his automobiles - have it move in relation to
> the steering wheel?

BMW have "adaptive headlights" on the Series 7 (1MB)

http://www.bmw.com/bmwe/products/automobiles/7er/pdf/7er_sedan.pdf

Saw one on TV a while ago. Pretty nifty having the headlights
shining where you're steering, not where the car's pointing

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

2004\01\04@014052 by Tal

flavicon
face
The amazing thing is that the French car maker Citroen thought on this many
many years (on DS/GS models) ago but abandon it.
And now BMW have a it.
French car are shit in my opinion (and I have 1 to prove it) but are very
innovative.

Tal

{Original Message removed}

2004\01\04@015821 by Picdude

flavicon
face
Approx 5-6 yrs ago, I rented an American car that had auxiliary lights on each front corner, and pointed outwards and forward.  These came on (individually) when the appropriate turn signal was switched on.  Worked pretty well.  Can't remember which car it was though.

Cheers,
-Neil.


On Sunday 04 January 2004 12:31 am, Jinx scribbled:
{Quote hidden}

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

2004\01\04@023553 by Jinx

face picon face
> The amazing thing is that the French car maker Citroen
> thought on this many many years (on DS/GS models) ago
> but abandon it

Thanks for reminding me. I knew I'd seen adaptive headlights
recently but couldn't think where - it was a DS on the BBC's
Top Gear program last week. They did have some good things
to say about it and mentioned some of Citroen's innovations

http://www.bbc.co.uk/topgear/prog3/bestlooker.shtml

"New presenter Richard Hammond's vote is for the Citroen
DS (pictured bottom left), which was launched in 1955. Light
years ahead of its time, the DS changed the direction of car
design when it was unveiled, and 12,000 orders were placed
almost immediately"

I don't think they mentioned that it, I believe, can run on only 3
wheels because of the smart suspension

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

2004\01\04@025706 by Herbert Graf

flavicon
face
> Approx 5-6 yrs ago, I rented an American car that had auxiliary
> lights on each
> front corner, and pointed outwards and forward.  These came on
> (individually)
> when the appropriate turn signal was switched on.  Worked pretty
> well.  Can't
> remember which car it was though.

       Don't know about others, but my 1988 Olds Delta 88 has that. TTYL

----------------------------------
Herbert's PIC Stuff:
http://repatch.dyndns.org:8383/pic_stuff/

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

'[PIC] : car headlight control'
2004\01\04@061343 by Tim ODriscoll

flavicon
face
On Sun, 4 Jan 2004 TakeThisOuTreinaldoKILLspamspam@spam@IHUG.CO.NZ wrote:
> maybe it's not too different, but i'll just have a pot to
> adjust how far the pop-up headlights will open/close, but it
> won't be connected to the sterring wheel.

Can you use a rotary encoder on the human side? That should simplify the
software a bit..

Cheers,

Tim

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

'[OT] : car headlight control'
2004\01\04@123028 by p.cousens

flavicon
This was fitted to some DS models and later on all SM models (the SM was
manufacured from 1971-1973)
Never on the GS or any other models

As for for being shit, citroens list of inovations is rivaled by no one
Double helix gears (that's what the badge represents)(1890's)
Since 1934 ALL models made with front wheel drive
Tubeless tyres
Self leveling suspension (1950's)
Load compensated rear braking (1950's on )
Inboard front brakes (2CV, GS, ami & dyane)
Zero geometry steering (the king-pin is inclined further to intersect
the ground on the center line of the wheel)
So the occupants live through a high speed front wheel blowout

To list a few...........

The last citroens were the GS, CX, and 2CV. The AX, BX and onward are
Peugeot's with citroen badges,
Not to be confused with Andre Citroen's creations

{Original Message removed}


'[EE]: Automobile LED headlights'
2006\11\01@152306 by Charles Craft
picon face
Interesting - I would have figured they would be wired so that multiple failures still allowed the lamp to function.

http://www.usatoday.com/money/autos/2006-10-31-headlight-usat_x.htm

<snip>

The National Highway Traffic Safety Administration says LED headlights are legal if they meet the illumination regulations applied to all other types of headlights in the USA.

They also have to be wired so that if one tiny LED fails, the whole light goes out. NHTSA says that prevents motorists from unknowingly driving with reduced illumination.

<snip>


2006\11\01@160853 by Peiserma

flavicon
face
piclist-bounces@mit.edu wrote:
> They also have to be wired so that if one tiny LED fails, the
> whole light goes out. NHTSA says that prevents motorists from
> unknowingly driving with reduced illumination.

So they prefer driving with no lights over dim lights? Hmmm.

On a distantly related note: car problems forced me to tear into my dash
yesterday. My remote-starter unit dated 1993 is controlled by a
PIC16C54...




2006\11\01@162523 by PicDude

flavicon
face
On Wednesday 01 November 2006 14:23, Charles Craft wrote:
> ...
>
> They also have to be wired so that if one tiny LED fails, the whole light
> goes out. NHTSA says that prevents motorists from unknowingly driving with
> reduced illumination.

Very odd, I would've expected that considering the cost of the LEDs, adding
some monitoring to indicate blown LED-string(s) would've been relatively
insignificant, and would be safer (IMHO) if you blow one LED on a dark road
in the middle of nowhere some night.  The NHTSA should've at least allowed
this option.

Cheers,
-Neil.

2006\11\01@163035 by Jinx

face picon face
> Interesting - I would have figured they would be wired so that multiple
> failures still allowed the lamp to function.

Maybe a LED on the dash to say a LED in the headlight has failed ;-))

> http://www.usatoday.com/money/autos/2006-10-31-headlight-usat_x.htm

> They also have to be wired so that if one tiny LED fails, the whole
> light goes out. NHTSA says that prevents motorists from unknowingly
> driving with reduced illumination

Say one headlight goes out and you get pulled over in the next 5
minutes by a cop for that. A time and date stamp on the failure
would be nice, so you didn't get a ticket

I can see their reasoning. On a consumer program a few years ago
was this story. A woman was booked in for a driving test and had
paid the $80 for the appointment. Before the test, the examiner
checked the car and failed it because the rear window brake light
didn't go on. Both tail brakes were OK. She explained that she'd
bought the high light the day before but hadn't connected it yet. She
lost the appointment and the $80, and was appealing, through the
program, to get the $80 back. The answer was that if there's a brake
light there, other drivers expect to see it go on, so she didn't get
the $80 back. It didn't matter that the car had functioning factory
brake lights

2006\11\01@172833 by Russell McMahon

face
flavicon
face
> ... Before the test, the examiner
> checked the car and failed it because the rear window brake light
> didn't go on. Both tail brakes were OK. She explained that she'd
> bought the high light the day before but hadn't connected it yet.
> She
> lost the appointment and the $80, and was appealing, through the
> program, to get the $80 back. The answer was that if there's a brake
> light there, other drivers expect to see it go on, so she didn't get
> the $80 back. It didn't matter that the car had functioning factory
> brake lights

In NZ cars 1st registered after a certain year (~~1990?) have to have
high level brake lights. Cars 1st registered before that don't have to
have them BUT if they are fitted they must work. My daughter's  car
falls in the latter category. At a recent checkup (= WOF = Warrant of
Fitness) the high level light's bulb was dead. The eaxminer advised
her to either replace the bulb or to remove the light.

______________

(one of) My car(s)  (an old Subaru Leone wagon) has 4 headlights plus
2 factory fitted auxiliary fog lights . The fog lights are covered
with protective plastic covers. They don't work and have not done so
since I bought the car over a year ago. At the last WOF test (2nd or
3rd since I've had the car) they said the fog lights must be working
or be removed by next WOF test 6 months hence. They noted this ob
their computer record - available to all WOF testers country wide. New
rules apparently. Have to fix them I guess.
_______________

I can actually sympathise with the intent of both these rules, even
though they may seem arbitrary and stupid.

A high level brake light can be much easier to see than std rear
lights and a motorist in traffic could indeed be depending on a light
which is visible but non functional. Fog lights which are illegally
adjusted so that they dazzle oncoming cars could be claimed to be non
functional during a WOF test and then enabled thereafter - or just
switched on using an accessory switch as is often enough the case with
fog lights. The really keen will adjust lights down for WOFs and up
again afterwards but most people don't go to those extremes.

I have vague memories that our lovely 8 inch? 100 Watt Cibie Super
Oscar driving lamp which we used long ago for night-time car trialling
became illegal after some years of use because we had only one fitted
(all you needed !!!) and the regs were changed so that you had to have
a pair so that 3-eyes would not confuse people in some manner. As we
only used it on long straights or in dark countryside where its
stunning illumination was needed, and never used it against oncoming
cars (lest they catch fire in the beam :-) ) the requirement was a
nonsense. [[Just perhaps and maybe it was also occasionally useful on
main highways to remind oncoming cars that THEIR lights were still on
full beam]].  I vaguely recall that the lamp thereafter used to become
non-functional for a short period around WOF time and that the testers
never complained (and probably understood). But, that was long ago and
that part of the memory may be a synthesised one.  The lamp is real
enough, but it currently lives on a shelf in my basement.



       Russell

2006\11\01@173108 by Russell McMahon

face
flavicon
face
> Maybe a LED on the dash to say a LED in the headlight has failed
> ;-))

On and green when lamp on.
Off and dark when lamp off.
Fail safe* against indicator LED failure.



       Russell

* Most people don't understand what "fail safe" really means.


2006\11\01@195046 by Sean Schouten

face picon face
On 11/1/06, PicDude <.....picdude2RemoveMEspamavn-tech.com> wrote:
>
>
> Very odd, I would've expected that considering the cost of the LEDs,
> adding
> some monitoring to indicate blown LED-string(s) would've been relatively
> insignificant, and would be safer (IMHO) if you blow one LED on a dark
> road
> in the middle of nowhere some night.  The NHTSA should've at least allowed
> this option.
>


Well... in that single scenario, a BIG plus would be that a car has not one,
but two headlights. Still a bummer though!


Sean.

2006\11\01@220012 by Jim Korman

flavicon
face
Charles Craft wrote:
> Interesting - I would have figured they would be wired so that multiple failures still allowed the lamp to function.
>
> http://www.usatoday.com/money/autos/2006-10-31-headlight-usat_x.htm
>
> <snip>
>
> The National Highway Traffic Safety Administration says LED headlights are legal if they meet the illumination regulations applied to all other types of headlights in the USA.
>
> They also have to be wired so that if one tiny LED fails, the whole light goes out. NHTSA says that prevents motorists from unknowingly driving with reduced illumination.
>
> <snip>
>
>
>  
I note in the article they mention the long life time of an LED.
BUT, if one LED fails the unit, what does that do to the
potential life span of the unit?

Jim

2006\11\01@222731 by David VanHorn

picon face
>
>
> I note in the article they mention the long life time of an LED.
> BUT, if one LED fails the unit, what does that do to the
> potential life span of the unit?


Makes it much less reliable.

I smell special interest intervention here..


If I had a headlight with a significant number of LEDs in it, and I found
out that I had to replace the whole thing because ONE blew, I'd be pissed.
If you have 10 leds, then that's only 10% down if one fails, and even a
slightly dirty headlight is down that much.

2006\11\01@223053 by David VanHorn

picon face
www.usatoday.com/money/autos/2006-10-31-headlight-usat_x.htm

gargoyle delivered this link along with this email discussion.

2006\11\01@223439 by Herbert Graf

flavicon
face
On Wed, 2006-11-01 at 22:27 -0500, David VanHorn wrote:
> >
> >
> > I note in the article they mention the long life time of an LED.
> > BUT, if one LED fails the unit, what does that do to the
> > potential life span of the unit?
>
>
> Makes it much less reliable.
>
> I smell special interest intervention here..
>
>
> If I had a headlight with a significant number of LEDs in it, and I found
> out that I had to replace the whole thing because ONE blew, I'd be pissed.
> If you have 10 leds, then that's only 10% down if one fails, and even a
> slightly dirty headlight is down that much.

Well, the way I see it is as long as the headlight outputs at least the
minimum required amount of illumination you are OK.

So, design the headlight to put out say 150% of the minimum, then you
can have 33% of the LEDs fail before you're required to "shut off" the
headlight.

TTYL

2006\11\01@224954 by David VanHorn

picon face
Article said they would cost even more than the HID lights.
OUCH!

2006\11\02@003936 by Tony Smith

picon face
{Quote hidden}

David might be right.  Current regulations are that the headlight must
illuminate to a certain distance, 30 metres or so.  Here's a US article that
says 15 feet - http://www3.whdh.com/features/articles/hank/30/.

There's no reason to fiddle with the existing rules.

I think it's far safer to have a slightly dimmer light than no light at all.
Also, it works both ways, people can see the car with the lights on.

Might be a moot point eventually as LEDs get brighter.

Tony

2006\11\02@114537 by Mike Hord

picon face
> If I had a headlight with a significant number of LEDs in it, and I found
> out that I had to replace the whole thing because ONE blew, I'd be pissed.

No, you (being who you are) would crack it open, pull the LED, and replace
it from one purchased at Digikey.  As would (I hope) most of us.

A friend of mine did this with his brake light strip.  It was one of those with
LEDs, and he found the faulty one and replaced it.

I agree that it is kind of stupid- to me, part of the point of using a multi-LED
bank is redundancy against failure.  I'd say it should be designed with a
couple of extra LEDs (??? how many are we talking about, here?) which
kick in upon failures to keep the light level up, but below a certain point,
the whole thing dies.

Mike H.

2006\11\02@120237 by David VanHorn

picon face
On 11/2/06, Mike Hord <KILLspammike.hordspamTakeThisOuTgmail.com> wrote:
>
> > If I had a headlight with a significant number of LEDs in it, and I
> found
> > out that I had to replace the whole thing because ONE blew, I'd be
> pissed.
>
> No, you (being who you are) would crack it open, pull the LED, and replace
> it from one purchased at Digikey.  As would (I hope) most of us.


This could end up like toner carts, with embedded uPs working to prohibit
such a repair, or a hardware solution that fries all the other leds.

I agree that it is kind of stupid- to me, part of the point of using a
> multi-LED
> bank is redundancy against failure.  I'd say it should be designed with a
> couple of extra LEDs (??? how many are we talking about, here?) which
> kick in upon failures to keep the light level up, but below a certain
> point,
> the whole thing dies.


Yeah, that's how I'd do it.. In a smart car, the headlight could in theory
communicate it's status, and warn that it's run out of spare LEDs, or
something like that.

2006\11\02@120812 by Michael Rigby-Jones

picon face


{Quote hidden}

Christmas tree lights manage this without any extra circuitry.  They even kill themselves after too many bulb have blown!

Regards

Mike

=======================================================================
This e-mail is intended for the person it is addressed to only. The
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,
forwarding, printing or copying of this message is strictly prohibited.
No part of this message can be considered a request for goods or
services.
=======================================================================

2006\11\02@130132 by David VanHorn

picon face
>
> Christmas tree lights manage this without any extra circuitry.  They even
> kill themselves after too many bulb have blown!


True, but the filament lets go and allows the supports to spread and contact
a ring of wire.
Can't do that in an LED.

2006\11\02@153732 by Alan B. Pearce

face picon face
>I have vague memories that our lovely 8 inch? 100 Watt Cibie Super
>Oscar driving lamp which we used long ago for night-time car trialling
>became illegal after some years of use because we had only one fitted
>(all you needed !!!)

I have a pair of those somewhere - one spot and one driving lens. made going
away to conference at Easter time a cinch. Driving through winding roads in
the wairapa became a real nice with very little other traffic around.

2006\11\02@155718 by Shawn Wilton

picon face
I sense an emerging business opportunity repairing expensive LED headlights
on the cheap!



On 11/2/06, David VanHorn <.....dvanhornEraseMEspammicrobrix.com> wrote:
{Quote hidden}

> -

2006\11\02@201156 by Michael Rigby-Jones

picon face


>-----Original Message-----
>From: spamBeGonepiclist-bouncesspamRemoveMEmit.edu [.....piclist-bouncesEraseMEspammit.edu]
>Sent: 02 November 2006 17:19
>To: Microcontroller discussion list - Public.
>Subject: Re: [EE]: Automobile LED headlights
>
>
>>
>> Christmas tree lights manage this without any extra circuitry.  They
>> even kill themselves after too many bulb have blown!
>
>
>True, but the filament lets go and allows the supports to
>spread and contact a ring of wire. Can't do that in an LED.
>

I knew how it worked, was just joking really.  However, given the very high cost of these headlights, some "smarts" to alert the driver to a failed array of LEDs really should have been included.  It could even throw up a fault code on the OBD system.

Cheers

Mike

=======================================================================
This e-mail is intended for the person it is addressed to only. The
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,
forwarding, printing or copying of this message is strictly prohibited.
No part of this message can be considered a request for goods or
services.
=======================================================================

2006\11\02@201451 by Russell McMahon

face
flavicon
face
> I agree that it is kind of stupid- to me, part of the point of using
> a multi-LED
> bank is redundancy against failure.  I'd say it should be designed
> with a
> couple of extra LEDs (??? how many are we talking about, here?)
> which
> kick in upon failures to keep the light level up, but below a
> certain point,
> the whole thing dies.

One out all out can also be viewed as stupidly PC.
Tungsten bulbs degrade in output across lifetime with no suggestion
that they must be replaced prior to absolute failure. That said a
fully parallel LED array may take decades of use to dwindle to the
all-out point.



       Russell

2006\11\02@224240 by Tony Smith

picon face
> David might be right.  Current regulations are that the
> headlight must illuminate to a certain distance, 30 metres or
> so.  Here's a US article that says 15 feet -
> http://www3.whdh.com/features/articles/hank/30/.


Sigh.  115 feet.  Doh.

And in addition, I don't think headlights are tested in Australia either.
Their aim is checked, but I'm not sure on brightness.  How hard is it to
wave a lux meter around?

Tony

2006\11\03@004740 by Mario Mendes

flavicon
face
>> David might be right.  Current regulations are that the
>> headlight must illuminate to a certain distance, 30 metres or
>> so.  Here's a US article that says 15 feet -
>> http://www3.whdh.com/features/articles/hank/30/.
>
>
>Sigh.  115 feet.  Doh.
>
>And in addition, I don't think headlights are tested in Australia either.
>Their aim is checked, but I'm not sure on brightness.  How hard is it to
>wave a lux meter around?
>
>Tony


How hard???  Well, I estimate that it'll take 356 government employees, 67
months to write hundreds of pages to document the what/why/when/where/how to
do it and cost millions in taxes just because someone decided it needed to
become a law/regulation.

No offense to any government workers in the list (if any) of course ;)


-Mario




2006\11\03@035930 by Howard Winter

face
flavicon
picon face
Tony,

On Thu, 2 Nov 2006 16:58:08 +1100, Tony Smith wrote:

{Quote hidden}

Over here headlight alignment is checked on a machine but not brightness, but they did mention on my car's last test that they were dimmer than
they should be - I suspect a dodgy earth connection - but they didn't fail it, and as long as they are substantially working I don't think they can.  I
know they can fail it for being *too* powerful - I believe 55W is the limit, but you can get 100W bulbs "for offroad use only".

Cheers,


Howard Winter
St.Albans, England


More... (looser matching)
- Last day of these posts
- In 2006 , 2007 only
- Today
- New search...