Searching \ for 'Identifying Bingo Balls' 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=identifying+bingo
Search entire site for: 'Identifying Bingo Balls'.

Truncated match.
PICList Thread
'Identifying Bingo Balls'
1998\10\07@200359 by Sean Breheny

face picon face
Hi all,

I have received an email in spanish from someone in Spain who monitors the
piclist, but is usually unable to ask questions because of the language
barrier. So, once again, I have translated the message into english and
will translate any relevant replies back to spanish for him. He is Jose
Antonio Gracia.

Here is the translated text:

Piclist friends:

       In Spain, the game of bingo is legal and there are businesses which offe
r
it to people who want to play.
       I have a program for these businesses, which works in MSDOS, that plays
with all of the cards sold in the room, calculates the prizes to
distribute, and tells the person presiding over the game when there is a
winner (to avoid cheating).
       Now, I am looking for a way to identify the ball which gets extracted[fr
om
the randomized pot], which is shown on TV monitors (They are ping-pong balls).
       I had thought of two possible forms of identification:

       1. To mark the balls with colors and identify them. But this system rais
es
the price of the balls excessively,

       2. - To put a bar code on them. This has many possibilities, but bar cod
e
scanners
need a minimum size for the code which is very large for the available
space. Because of this, I was thinking of inventing my own code, since it
only needs 90 combinations.


       The question is:

       Has someone done something with PICs and bar codes and can he help me?

       I don't know how the scanner detects the bar code, nor whether it is
adaptable to a PIC, or I can position an LED with a phototransistor and
identify the code myself [without a premade scanner], provided that it can
be in any position, for which I will probably need three detectors.

Greetings, and thanks in advance,

Jose Antonio Gracia

spam_OUTjgraneTakeThisOuTspamcolon.net
http://www.geocities.com/SiliconValley/Pines/7097

[END OF TRANSLATED MESSAGE]

I and Jose would greatly appreciate it if you would take a look at this. I
know its annoying to read a translated message (especially one as rougly
translated as this! Hey, I'm an engineering student, I take spanish, but
that is not a core course <G>) However, I get a fair number of such
translation requests from fellow PICers who only speak spanish.

Thanks,

Sean



+--------------------------------+
| Sean Breheny                   |
| Amateur Radio Callsign: KA3YXM |
| Electrical Engineering Student |
+--------------------------------+
Save lives, please look at http://www.all.org
Personal page: http://www.people.cornell.edu/pages/shb7
.....shb7KILLspamspam@spam@cornell.edu  Phone(USA): (607) 253-0315 ICQ #: 3329174

1998\10\07@204810 by Dave VanHorn

flavicon
face
>        Now, I am looking for a way to identify the ball which gets
extracted[from
>the randomized pot], which is shown on TV monitors (They are
ping-pong balls).
>        I had thought of two possible forms of identification:
>
>        1. To mark the balls with colors and identify them. But this
system raises
>the price of the balls excessively,
>
>        2. - To put a bar code on them. This has many possibilities,
but bar code
>scanners
>need a minimum size for the code which is very large for the
available
>space. Because of this, I was thinking of inventing my own code,
since it
>only needs 90 combinations.



I've done barcode recognition, making up your own code is a BAD idea.
It's not at all trivial to get something that works well in the real
world.  Substitution errors would be a disaster on wheels.

You could adapt UPC/EAN or code 39 to this, but you have a bigger
problem in that you need to orient the balls so that the reader can
see the code.  This could be done, but raises the cost again.
Suppressed EAN is small, and you can actually shrink the code quite a
bit and still read it, if your printing is accurate. Laser marking
would be a good idea.

Some sort of PC based image recognition ought to do well at simple
jobs like "B9" printed in black on a ball, again though, it would need
to be moderately well oriented.

Offhand, I'm not coming up with anything that hugely workable, cheap,
and that won't give you a horrible problem in altering the weight of
the balls other than an optical mark like printing or barcoding.

If the users would accept it, a microcontroller could eliminate the
balls, and make the whole thing a non-problem.  Although I've been
flamed before for suggesting this, an alpha radiation source and
detector enclosed in a metal box, would give you a provably random
time between detected particles, and all you'd need then is a counter
spinning away to say which "ball" is picked, and a list of previously
picked "balls" to tell the randomizer to "pick again" when it comes up
with the same number in a given set.  Alpha emitters (like from a
smoke detector) can't penetrate even a single sheet of paper, so I
can't understand the very vocal objections I've seen to this approach.
AFAIK, radioactive decay is still provably random, or at least very
unlikely to be influenced by anything in the average bingo hall.
Alpha particles are helium atoms with no electrons.

1998\10\07@205904 by Justin Crooks

flavicon
face
I prefer using a pseudo-random sequence.  There's no way to cheat with a
Geiger counter randomizing everything!


{Quote hidden}

1998\10\07@211544 by Dave VanHorn

flavicon
face
>I prefer using a pseudo-random sequence.  There's no way to cheat
with a
>Geiger counter randomizing everything!


Thanks :)

1998\10\08@064605 by g.daniel.invent.design

flavicon
face
Sean,
Your Spanish friend can use proximity I.D. in each ball,
Try Temic.

Sean Breheny wrote:
>
cut
>         Now, I am looking for a way to identify the ball which gets extracted[
from
> the randomized pot], which is shown on TV monitors (They are ping-pong balls).
cut
> Thanks,
> Sean

1998\10\08@064624 by Michael Hagberg

flavicon
face
take a look at the "2 of 5 interleved" format it would be a very small code.
michael

You may leave the list at any time by writing "SIGNOFF PICLIST" in the
   body of a message to LISTSERVspamKILLspamMITVMA.MIT.EDU.


>
>        2. - To put a bar code on them. This has many possibilities, but
bar code
>scanners
>need a minimum size for the code which is very large for the available
>space. Because of this, I was thinking of inventing my own code, since it
>only needs 90 combinations.
>
>

1998\10\08@064638 by Frank A. Vorstenbosch

flavicon
face
Dave VanHorn wrote:
> [...] Although I've been
> flamed before for suggesting this, an alpha radiation source and
> detector enclosed in a metal box, would give you a provably random
[...]
> AFAIK, radioactive decay is still provably random, or at least very
> unlikely to be influenced by anything in the average bingo hall.
> Alpha particles are helium atoms with no electrons.

Yes, radioactive decay is provably random, but so is junction noise.
Here's a simple noise generator which I happen to have on a bit of
breadboard on my desk this week.

                 +12
                  |
                 5.6k                  ,-- 6M8 --+
                  |                    |         |
 ,------+-- 47k --+-- 100nF --+-- 22k -+- -      |
 |      |         |           |           opamp -+--- OUT
100nF   E         C           +-- 22k -+- +
 |        B --- B                      |     1/2 LM6482
GND     C         E                   1nF     (at +5V)
          Q1      |  Q2                |
                 GND                  GND

Q1 and Q2 both small signal NPN transistors; I'm using BC547s now, but I
am going to try using faster transistors in the hope of getting higher
frequency noise from it.  As it is, it will generate about 100kbps true
random data when coupled to a Von Neumann equalizer and some proprietry
other circuitry.

This circuit is due to Winfried Hill, here is part of his message in
sci.electronics.components last May:

{Quote hidden}

Frank
------------------------------------------------------------------------
Frank A. Vorstenbosch     <SPAM_ACCEPT="NONE">    Phone: 0181 - 636 3000
Electronics and Software Engineer                 Mobile: 0976 - 430 569
Eidos Technologies Ltd., Wimbledon, London        Email: .....favKILLspamspam.....eidos.co.uk

1998\10\08@064647 by Geoff Wootton

flavicon
picon face
Hi Sean, Jose

My guess is the only simple, cheap solution to this problem is the humble
numeric keypad that the bingo ball operator uses to key in the number. May
sound clumsy and low-tech, but keying in 2 digits is probably much quicker
than orienting the ball through a code reader and trying to get it to read
a curved surface - look at the number of mis-reads that supermarket check-out
people get when trying to read in less than flat bar codes.

Geoff.

1998\10\08@082340 by Harrison Cooper

flavicon
face
has anyone mentioned RFID?

1998\10\08@083207 by Reginald Neale

flavicon
face
How about this: Divide the surface of each ball into octants. Use four
colors, e.g. red, green, blue, no color (white). Four octants will always
be visible. Use scanning to decode color combinations = 3^4 = 243 possible
combinations. It would be possible to print the number on the ball in
addition so it would be human-readable.

Reg Neale

1998\10\08@083415 by Walter Banks

picon face
>         2. - To put a bar code on them. This has many possibilities, but
b
> bar code  scanners  need a minimum size for the code which is
> very large for the available  space. Because of this, I was thinking
> of inventing my own code, since it  only needs 90 combinations.

There are plenty of very good standard barcode formats that would work
well.

I2of5 is a standard barcode format that is very easy to read. It was
developed by Intermec for encoding the digits 0 to 9. The name
Interleaved two of five comes from the format of the code. Each symbol
contains a pair of digits the first is encoded in the bars the second is
encoded in the interleaved spaces. Each character has three narrow
elements and two wide elements. The full specification is found in
MHI/AIM USD-1.

Reading this type of code is very easy even with hand scanners and
a small processor ie 16c54. Make a list of time vs transitions from the
wand. separate the white and dark bars. for each set of times (five
for white and five for dark)  look for the two longest bars and do a
table lookup each character.

Barcode wands generate TTL level outputs and I have never found
anyone who was able to scan faster than 42inches/second

It is more complicated but you can probably write OCR code to read
the number from the ball just by digitizing the video sent tio the TV
monitors You are already using a PC and video digitizers are are
readily available.


Walter Banks
http://www.bytecraft.com

1998\10\08@095548 by Dave VanHorn

flavicon
face
>take a look at the "2 of 5 interleved" format it would be a very
small code.
>michael


and about the worst for substitution errors.

1998\10\08@095602 by Dave VanHorn

flavicon
face
>Yes, radioactive decay is provably random, but so is junction noise.
>Here's a simple noise generator which I happen to have on a bit of
>breadboard on my desk this week.


What happens to it's randomity if I apply a regular RF pulse?
I suppose if enough shielding is used...

1998\10\08@100009 by Dave VanHorn

flavicon
face
>I2of5 is a standard barcode format that is very easy to read. It was
>developed by Intermec for encoding the digits 0 to 9. The name
>Interleaved two of five comes from the format of the code. Each
symbol
>contains a pair of digits the first is encoded in the bars the second
is
>encoded in the interleaved spaces. Each character has three narrow
>elements and two wide elements. The full specification is found in
>MHI/AIM USD-1.


It's also very easy to get substitution errors, which would be pure
hell in this application.

I like the eight-colored ball idea best.
Could it be read by illuminating with red, green, and blue leds and
measuring the reflectance?
That would also be visually cool, another plus point with this type of
thing.

1998\10\08@103419 by Peter L. Peres

picon face
On Wed, 7 Oct 1998, Dave VanHorn wrote:

> Some sort of PC based image recognition ought to do well at simple
> jobs like "B9" printed in black on a ball, again though, it would need
> to be moderately well oriented.

Yes, but how do you explain a bluescreen that happens at the wrong moment
;) ? This is about $money$ remember ?

> flamed before for suggesting this, an alpha radiation source and

Flamed by whom ? BTW you don't need an alpha source, it's enough if you
use a Geiger tube as is and count the interval between clicks in usecs or
so (or capture a running timer when a click occurs). Advantage: your luck
will literally depend on the stars, or more exactly on the
rise/setting/angle of cellestial radiation sources for your location ;)

BTW a digitally integrating Geiger counter is an excellent PIC project
imho. The Geiger output is a nice strong pulse that can be read directly
by a CMOS input and the high voltage can be generated using a squarewave
output by your PIC truly and a VFET to drive a small transformer. Any1 ?

Peter

1998\10\08@103422 by Peter L. Peres

picon face
On Wed, 7 Oct 1998, Sean Breheny wrote:

> Hi all,
>
> I have received an email in spanish from someone in Spain who monitors the
> piclist, but is usually unable to ask questions because of the language
> barrier. So, once again, I have translated the message into english and
> will translate any relevant replies back to spanish for him. He is Jose
> Antonio Gracia.
>
>         1. To mark the balls with colors and identify them. But this
> system raises the price of the balls excessively,

Why ? Dumping ping-pong balls into a vat of paint should not be a serious
problem. After all, Easter Eggs pass this test every year. Ok, you need a
different paint base, but it is the same idea. Getting 90 consistent
nuances of color right, and consistent over time, is another matter.

>         2. - To put a bar code on them. This has many possibilities, but
> bar code scanners need a minimum size for the code which is very large
> for the available space. Because of this, I was thinking of inventing my
> own code, since it only needs 90 combinations.

90 combinations < 2^7 == at least 7+1 symbols to print. With ECC for such
a $$$-related application, at least 12. For a RZ code, double that == 24.
For ease of printing and detection, the symbols should be linear, binary,
and not smaller than 0.5 mm each, giving a code area length of at least 12
mm, and probably as wide. You'd probably print more than one copy of it
per ball.

You have to think about the fact that printing anything on a ball shaped
surface is a major challenge, even if it is a barcode (that can be printed
by rotating the ball in front of the head, for example, together with a
human-readable number, with an ink-jet printer). I can see some
possibilities here, but the ball printer will be a major project imho.

> Has someone done something with PICs and bar codes and can he help me?

I have done a prototype barcode reader with a PIC 54 and a LM 324. It does
not care about the barcode system used and has RS232 output. With the head
I'd used it worked for bars down to 0.5 mm wide each, but 0.5-1 mm is a
better idea. If you want to know more, please contact me privately. The
reader is meant to be of the swiped wand type but it can be used with an
auto-scanned unit.

>         I don't know how the scanner detects the bar code, nor whether it is
> adaptable to a PIC, or I can position an LED with a phototransistor and
> identify the code myself [without a premade scanner], provided that it can

Not a good idea. Bar code reader heads are special. Almost none work 'from
any position', excepting automatic conveyor belt packet sorters, which are
a little bit over your budget I presume (they use 3 to 5 CCD cameras to
look at a package from all 5 free sides and analyze the image for the
barcode using a computer). Non-laser heads need to get very close to the
object (0.5 cm and less), or use OCR-related technology and 2-dimensional
raster scan CCDs (expen$ive like the conveyor system).

> be in any position, for which I will probably need three detectors.

imho start thinking about a channel, or tube, or through you drop the ball
into, such that it moves in front of a sensor(s). Otherwise I can see
problems that are not easily conquered. The other way is a laser scanning
barcode reader and the operator holding the ball in front of it, or one
of the expen$ive camera+image analysis methods.

Peter

1998\10\08@103950 by Reginald Neale

flavicon
face
>I like the eight-colored ball idea best.
>Could it be read by illuminating with red, green, and blue leds and
>measuring the reflectance?
>That would also be visually cool, another plus point with this type of
>thing.

Yes but they aren't very bright. Might be better to use incandescent lamp
and rotating filter to illuminate balls. Would also be "visually cool" and
could provide a sync pulse too.

You probably already know about 2D barcodes. Aren't they less alignment
sensitive than the regular kind?

Reg Neale

1998\10\08@111135 by Peter L. Peres

picon face
On Thu, 8 Oct 1998, Dave VanHorn wrote:

> I like the eight-colored ball idea best.  Could it be read by
> illuminating with red, green, and blue leds and measuring the
> reflectance?  That would also be visually cool, another plus point with
> this type of thing.

An eight-colored ball poses the indexing problem, i.e. where do you start
reading ? Also, you don't need 8 colors, you need 7 unique tokens (since
there is no way to establish an order), readable simultaneously (2^7 =
128). So it's more like representing 128 distinct colors on a surface.

By using color alone, you need to resolve about 3 degrees in the color
plane, and that's bad news. It is very hard to make ink that does that
cheaply, and the detection is not fun, let alone printing.

By using grayscale plus primary colors you can split off 4 levels of
grayscale (including white and black), plus a white reference area. This
cuts 2 bits off the 7, leaving 5 to be color coded. By giving each color 2
bits, you get 6 bits, one spare for parity/error checking (2+2+2+2=7+1),
or... se below.

This code can be represented by printing in 4-color print on the balls
(this is not easy - i.e. not cheap), a pattern like this, several times -
see below why and where:

- white background - also white reference - the bare ball

- a square or other shaped zone, printed with one of 4 gray levels, from
white to black. Can also be some other shape, but its surface must equal
the area of a zone (see below):

- three groups of two zones each, printable with a primary color or black
(or white) each.

- all four zones must be printed such, that a whole zone is visible
however you look at the ball, and no other zone is partially visible (at
the corners of a circumscribing tetrahedron projected on the sphere).
Because of the ambiguity such generated (when viewing from a point on a
perpendiculary from a touch point) there is a need for a second set of
patterns, with a code distinct from the 1st one's, printed on the touch
point positions, and encoding the same information. The 8th available bit
could be used for this (to encode the 2nd group).

- This system requires 2 distinct color patterns printed 4 times each on
each ball, at precise angles, there being 90 distinct combinations of
these. Ouch.

I make an educated guess by saying that this image can be converted into a
useful signal by shooting the scene with a color TV camera such that a
pattern fills at least 1/5 of the screen area, worst case, and all other
colors in the scene are neutral.

The white balance on the camera needs to be locked out, and the signal can
be analyzed using either a semi-analog sample and hold and quantization
method for Y and C yielding signals for A/D converters (yes, a PIC's A/Ds
would be enough), or digitized by a computer frame grabber and analyzed in
software (neater, but not a PIC project).

Only one ball should be in the image at any one time. Or at least only one
MOVING ball in the case of the digitizer.

There remains to be found a printer who will print 90 different patterns,
using 4-color printing, several times each, at relatively accurate angles,
onto ping-pong balls, at reasonable cost. Double-ouch.

So, a black/white pattern printed on each ball is a much better idea imho,
using the same TV camera and digitzer method for readout. You can still
paint the balls like easter eggs by dipping before or after printing, just
use transparent paint for good contrast ;)

Peter

1998\10\08@120329 by John Payson

flavicon
face
part 0 1868 bytes
I don't know how the UPS "bullseye barcodes" work, but the PDF-814
barcodes which is used for the USPS's computer-printable postage (among
other things) is more sensitive to alignment than 1D barcodes.  With
the 1D barcodes, all that is required is for the sensor sweep to pass
through both ends of the code (and everything between) and if the code
is printed sufficiently tall it's possible to be 30+ degrees off and
still scan successfully (many supermarket scanners have three beams which
scan at 60-degree angles relative to each other so they can read any
barcode that's facing them regardless of orientation).  For PDF-814 codes
each "character" is 14 pixels long by three (identical) pixels high; to
and the scanner must see a character in its entirety to read it.

Note that it's not necessary for the beam to hit an entire row of char-
acters in a single pass; there are three sets of characters (with set 1
used on rows 0, 3, 6, etc.; set 2 used on rows 1, 4, 7, etc.; and set
3 used on rows 2, 5, 8, etc.) so the scanner can tell when the beam
crosses from one row to another; in addition the scanner can assemble
pieces of the code read on subsequent passes and can use ECC to fill in
any gaps.  As a result, it's usually not especially hard to make an item
scan with a PDF-814 barcode but it's not nearly as forgiving as, e.g.,
a UPC code.

That having been said, I think your best bets are either to have the
operator key in the Bingo balls or else digitize the TV picture (since
you already have a camera pointed at the ball) and the operator's going
to rotate the ball so it's visible to that camera).  Alternatively, if
the balls are placed on a grid after they're drawn (any ball on the grid
must have come from the cage regardless of keying errors, etc.) it may
be possible to simply have a switch in each of the 75 grid spots.

1998\10\08@120342 by Peter L. Peres

picon face
On Thu, 8 Oct 1998, Reginald Neale wrote:

> You probably already know about 2D barcodes. Aren't they less alignment
> sensitive than the regular kind?

They are MORE sensitive when read with conventional 'eyes' (i.e. eye
line), and less so if read by OCR/CCD methods (imaging+analysis).

Peter

1998\10\08@120347 by Dave VanHorn

flavicon
face
>
>Yes, but how do you explain a bluescreen that happens at the wrong
moment
>;) ? This is about $money$ remember ?


Tell that to your ATM.

>> flamed before for suggesting this, an alpha radiation source and
>
>Flamed by whom ?

CCBBS crowd.  OOOH radioactive.. danger danger.. :-P

> BTW you don't need an alpha source, it's enough if you
>use a Geiger tube as is and count the interval between clicks in
usecs or
>so (or capture a running timer when a click occurs). Advantage: your
luck
>will literally depend on the stars, or more exactly on the
>rise/setting/angle of cellestial radiation sources for your location
;)


The advantage of an alpha detector is that it dosen't see rads outside
the can. I don't know if it's even possible at all to get an alpha to
penetrate a few mm of metal.  With a gamma detector, you could park a
thorium source near it and influence the rate..

1998\10\08@120354 by Dave VanHorn

flavicon
face
>You probably already know about 2D barcodes. Aren't they less
alignment
>sensitive than the regular kind?


Yes, but the readers are more expensive.

1998\10\08@131906 by Harold Hallikainen

picon face
       How about some sort of RFID approach?  Put a shoplifting tag with
a unique serial number in each ball?  Probably increses the cost of the
ball excessively...

Harold



Harold Hallikainen
EraseMEharoldspam_OUTspamTakeThisOuThallikainen.com
Hallikainen & Friends, Inc.
See the FCC Rules at http://hallikainen.com/FccRules and comments filed
in LPFM proceeding at http://hallikainen.com/lpfm

___________________________________________________________________
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com
or call Juno at (800) 654-JUNO [654-5866]

1998\10\08@131913 by Peter L. Peres

picon face
On Thu, 8 Oct 1998, Dave VanHorn wrote:

> >Yes, but how do you explain a bluescreen that happens at the wrong
> moment
> >;) ? This is about $money$ remember ?
>
> Tell that to your ATM.

I never have to, most of them here seem to be NCR and they don't have
smelly stuff in the CPU. The only thing that happens is, they run out of
$$ at the wrong time (long weekends etc). BUT the display set up at a
certain realtors window cycling through property pics (not PICs) shows a
nice L3.11fWg desktop about once every 3 days instead of the property ;)

> >> flamed before for suggesting this, an alpha radiation source and
> >Flamed by whom ?
> CCBBS crowd.  OOOH radioactive.. danger danger.. :-P

Who or what is/are CCBBS ?

{Quote hidden}

The rate does not matter, the ratio between rate and resolution of timing
between clicks does, and that only because your (our) measurements are
digital (i.e. quantified with a fixed rate). So if you park an old watch
or a power triode near the unit all you get is reduced resolution, the
randomness (almost) remains.

anyway, I like the idea of getting the stars into the picture very much ;)
How much for a Geiger tube for weak alpha ? I'm looking for something that
gives 10-30 clicks per minute for background. There aren't any on sale
here.

Peter

1998\10\08@134333 by Dave VanHorn

flavicon
face
>> CCBBS crowd.  OOOH radioactive.. danger danger.. :-P
>
>Who or what is/are CCBBS ?

Sorry, Circuit Cellar BBS crowd


>anyway, I like the idea of getting the stars into the picture very
much ;)
>How much for a Geiger tube for weak alpha ? I'm looking for something
that
>gives 10-30 clicks per minute for background. There aren't any on
sale
>here.


For alpha, it's a large area diode, you won't be seeing any stellar
alphas, they can't make it through the soup.  Gamma is what you're
thinking of.. Electronics Goldmine had a small tube for sale (and a
cheap counter kit)  What background rate you see is up for grabs
though.

I suppose an old propane lamp mantle in the box would give it enough
background.


OOOH!  Radioactive Ping-Pong balls!  Just dope each one with a
binary-encoded brew of seven isotopes, and use a differential counter
to tell which rad-bits are on.  128 unique codes possible.
The balls would be cheap, but the detector could be a bit pricey.

1998\10\08@142250 by Peter L. Peres

picon face
On Thu, 8 Oct 1998, Harold Hallikainen wrote:

>         How about some sort of RFID approach?  Put a shoplifting tag with
> a unique serial number in each ball?  Probably increses the cost of the
> ball excessively...

The weight and imbalance are the major problems if I remember the game of
bingo somewhat (never played).

Peter

1998\10\08@143116 by Peter L. Peres

picon face
On Thu, 8 Oct 1998, Dave VanHorn wrote:

> >anyway, I like the idea of getting the stars into the picture very much
> ;)  >How much for a Geiger tube for weak alpha ? I'm looking for
> something that >gives 10-30 clicks per minute for background. There
> aren't any on sale >here.
>
> For alpha, it's a large area diode, you won't be seeing any stellar
> alphas, they can't make it through the soup.  Gamma is what you're
> thinking of.. Electronics Goldmine had a small tube for sale (and a
> cheap counter kit)  What background rate you see is up for grabs
> though.

Last time I looked, there were NO Geigers on sale w/o data sheet, which
data sheet contains a plot of integrated clicks per dose (one curve for
each flavor of radiation, sometimes a fourth one for X) and another with
current/voltage curve for operating point setting. Geigers being what they
are, I strongly believe that there must be data sheets available
somewhere.

> I suppose an old propane lamp mantle in the box would give it enough
> background.

They're made with CeO, not ThO, as far as i know, and CeO can be had from
cigarette ashes ;) Do you smoke ? <g>

> OOOH!  Radioactive Ping-Pong balls!  Just dope each one with a
> binary-encoded brew of seven isotopes, and use a differential counter
> to tell which rad-bits are on.  128 unique codes possible.
> The balls would be cheap, but the detector could be a bit pricey.

I think that you would have to be patient to make out the profile for a
low enough radiation level, so as not to harm anyone. You'd also need a
lead-lined pit to quiet the background. Then, the croupier would be
accused of substituting balls in the pit...

Peter

1998\10\08@143525 by John Payson

flavicon
face
part 0 545 bytes
That reminds me of another notion: since different colored LED's
output different wavelengths (rather than combinations of RGB), it
may be possible to illuminate the ball with different-colored LED's
and read back the reflectance values.  You'd have to experiment to
find what colored dyes absorbed/reflected what wavelengths, but you
could get a lot more colors than just RGB.

Of course, there'd still be plenty of other tricky issues but illumin-
ating the ball with colored LED's could give you more data points to
work with than just RGB.

1998\10\08@144348 by Dave VanHorn

flavicon
face
>Last time I looked, there were NO Geigers on sale w/o data sheet,
which
>data sheet contains a plot of integrated clicks per dose (one curve
for
>each flavor of radiation, sometimes a fourth one for X) and another
with
>current/voltage curve for operating point setting. Geigers being what
they
>are, I strongly believe that there must be data sheets available
>somewhere.


Not in a $35 kit. All it had was parts and instructions. They may have
had specs on the tube back at EGM, but they didn't forward them to me.


>They're made with CeO, not ThO, as far as i know, and CeO can be had
from
>cigarette ashes ;) Do you smoke ? <g>


There may be other stuff, but there's thorium in there. IIRC it's to
keep the ashes hanging together better.
Funny, you never see rad warnings on the boxes, but they are
definitely hot. There is a tiny warning about not breathing the ashes
though.


>I think that you would have to be patient to make out the profile for
a
>low enough radiation level, so as not to harm anyone. You'd also need
a
>lead-lined pit to quiet the background. Then, the croupier would be
>accused of substituting balls in the pit...


Picky picky..

1998\10\08@172053 by Sean Breheny

face picon face
Hi all,

I'd like to thank everyone who has responded to this so far. I'll be
sending the translations of as much of this as I can to Jose soon.

I do have one additional question, quite OT, though:

At 12:39 PM 10/8/98 -0500, you wrote:
>I suppose an old propane lamp mantle in the box would give it enough
>background.

I have long heard that lamp mantles are radioactive, but I never knew why.
Can someone enlighten me? Does it have a purpose, or is it a side-effect of
a meterial added for other purposes?

Thanks,

Sean


+--------------------------------+
| Sean Breheny                   |
| Amateur Radio Callsign: KA3YXM |
| Electrical Engineering Student |
+--------------------------------+
Save lives, please look at http://www.all.org
Personal page: http://www.people.cornell.edu/pages/shb7
shb7spamspam_OUTcornell.edu  Phone(USA): (607) 253-0315 ICQ #: 3329174

1998\10\08@172857 by Dave VanHorn

flavicon
face
>At 12:39 PM 10/8/98 -0500, you wrote:
>>I suppose an old propane lamp mantle in the box would give it enough
>>background.
>
>I have long heard that lamp mantles are radioactive, but I never knew
why.
>Can someone enlighten me? Does it have a purpose, or is it a
side-effect of
>a meterial added for other purposes?


IIRC, they add thorium to the mantles to make the ash hold together
better.
They obviously wouldn't add radioactives without some benefit. Check
the box in the store though, there's no warnings, other than not to
breathe the ash. (I don't normally snort ashes anyway)

Pass a counter over one sometime!

1998\10\19@231827 by Sean Breheny

face picon face
Hi all,

I know that it has been a week or so since the last message on this thread,
but Jose sent me a message to translate and send to the list and I am only
getting to it now that I have a small respite from my studies. Again, sorry
for how late it is. It is primarily to thank all those who answered, but it
also brings up a few quick points:

Here it is:

>BEGIN TRANSLATION

Thanks,

       Dave VanHorn <@spam@dvanhornKILLspamspamCEDAR.NET>
       John Payson <KILLspamsupercatKILLspamspamCIRCAD.COM>
       Peter L. Peres <RemoveMEplpTakeThisOuTspamACTCOM.CO.IL>
       Harold Hallikainen <spamBeGoneharoldhallikainenspamBeGonespamJUNO.COM>
       Reginald Neale <TakeThisOuTnealeEraseMEspamspam_OUTSERVTECH.COM>
       Walter Banks <RemoveMEwalterspamTakeThisOuTBYTECRAFT.COM>
       Geoff Wootton <woottongEraseMEspam.....isdugp.bham.ac.uk>
       Frank A. Vorstenbosch <EraseMEfavspamEIDOS.CO.UK>
       Michael Hagberg <RemoveMEmhagbergEraseMEspamEraseMEI1.NET>
       Graham Daniel <RemoveMEg.daniel.invent.designspam_OUTspamKILLspamxtra.co.nz>
       Justin Crooks <RemoveMEjcrooksTakeThisOuTspamspamWYOMING.COM>

for your ideas

   Michel
   Walter
   Dave

Geoff:

>My guess is the only simple, cheap solution to this problem is the
>humble
>numeric keypad that the bingo ball operator uses to key in the number.

The problem is that the operator (who will be a young lady) who extracts
the ball, announces the number through the microphone and lights the
corresponding digit on a panel by pushing the right button.Consider the
case that a ball appears and she announces a different number than is on
the ball and lights a different light on the panel. We try to avoid such
errors by automating the process.


Reginal:
Peter:

The colors raise the cost of the balls. There is an obligation to change
the balls every 1000 games and they play between 100 and 110 games per day,
which equates to 1 set of new balls each 9 to 10 days.

John Payson:

Is there a clear chemical which has different indicies of refraction? It
could be a good idea to coat the balls with this and identify them by
refraction.


Its best that the system that we use be the most original possible. If
anyone already has a system which can be applied and is ready to be
commercialized, we can talk with him about it.

Regards,

       Jose Antonio Gracia
>END TRANSLATION

Thanks again guys,

Sean


+-------------------------------+
| Sean Breheny                  |
| Amateur Radio Callsign: KA3YXM|
| Electrical Engineering Student|
+-------------------------------+
Save lives, please look at http://www.all.org
Personal page: http://www.people.cornell.edu/pages/shb7
EraseMEshb7spamspamspamBeGonecornell.edu  Phone(USA): (607) 253-0315 ICQ #: 3329174

1998\10\20@053721 by Geoff Wootton

flavicon
picon face
Dear Sean/Jose

It's nice of you to reply to the suggestions; However I was curious in
your response to my comments, about the significance of the bingo caller
being a young lady?

{Quote hidden}

1998\10\20@094346 by Sean Breheny

face picon face
Hi Geoff,

At 10:35 AM 10/20/98 +0100, you wrote:
>Dear Sean/Jose
>
>It's nice of you to reply to the suggestions; However I was curious in
>your response to my comments, about the significance of the bingo caller
>being a young lady?
>

Sorry, I cannot help you directly there, I only tried to translate what
Jose sent me. I was doing it rather quickly, and there was a word in
spanish which I didn't recognize in there and I was translating very
quickly. I must be more careful in the future, PLEASE DON"T ASSUME THAT
ANYTHING PREJUDICIAL was ment by it, as I am not really sure what he meant
to say.

Sean

P.S. If anyone is interested, the oringinal spanish for that was:

> El problema es que el operador (suele ser una se–orita)  que
>extrae la bola, pronuncia el numero ante un microfono y enciende en un

"suele" is what I couldn't understand, and couldn't find in a dictionary (I
think its a typo), so I roughed it over. I know, not a good idea in
translation, but it was late and I didn't have time to ask him for a
clarification.

{Quote hidden}

+-------------------------------+
| Sean Breheny                  |
| Amateur Radio Callsign: KA3YXM|
| Electrical Engineering Student|
+-------------------------------+
Save lives, please look at http://www.all.org
Personal page: http://www.people.cornell.edu/pages/shb7
RemoveMEshb7KILLspamspamcornell.edu  Phone(USA): (607) 253-0315 ICQ #: 3329174

1998\10\21@113935 by Peter L. Peres

picon face
On Tue, 20 Oct 1998, Sean Breheny wrote:

> > El problema es que el operador (suele ser una señorita)  que
> >extrae la bola, pronuncia el numero ante un microfono y enciende en un
>
> "suele" is what I couldn't understand, and couldn't find in a dictionary (I
 ^^^^^^^
 'puede ser una senorita'
  ^^^^^
You probably got it right. A bout of dyslexia perhaps (d is near s and p
is near l. There remains the task of swapping them in the same word).

Peter

1998\10\21@113942 by Peter L. Peres

picon face
On Tue, 20 Oct 1998, Geoff Wootton wrote:

> Dear Sean/Jose
>
> It's nice of you to reply to the suggestions; However I was curious in
> your response to my comments, about the significance of the bingo caller
> being a young lady?

<VBG> it has subtle implications, hehehe. BTW, one must assume that if a
mistake can be made, then both possible mistakes will be made. The man
certainly did his homework on Murphy. I *like* people who think like this
;)

On topic: Since this is a large order I think that some arrangements with
a plastic factory are necessary. One set of balls every 10 days mandates
such a thing. They may even make a mold at such a rate. I think that 100
balls can be molded in a single go, and the mold would solve the marking
problem permanently. Remains to be determined, how to mark the balls. I
stand by my optical pattern method (not colored, e.g. 2-dimensional bit
pattern with ECC in it). I must confess that I've never played bingo and
most likely never will. There is no king to hunt, for starters ;)

Peter

1998\10\21@124134 by Sean Breheny

face picon face
Hi Peter,

At 06:43 PM 10/20/98 +0000, you wrote:
>You probably got it right. A bout of dyslexia perhaps (d is near s and p
>is near l. There remains the task of swapping them in the same word).

Actually, I found out after I said that I couldn't find it, that it
actually means "usually". I typed it into AltaVista's translator and that's
what it gave me. So it should read (usually it's a young lady). I don't
know why my dictionary doesn't have it!

BTW, you seem to be pretty good with languages! English, Hebrew, Spanish,
what else? I guess from your name that at least at some point in your
family tree you had relatives from Spain.

>
>Peter
>

Sean

+-------------------------------+
| Sean Breheny                  |
| Amateur Radio Callsign: KA3YXM|
| Electrical Engineering Student|
+-------------------------------+
Save lives, please look at http://www.all.org
Personal page: http://www.people.cornell.edu/pages/shb7
shb7STOPspamspamspam_OUTcornell.edu  Phone(USA): (607) 253-0315 ICQ #: 3329174

1998\10\21@125836 by Gabriel Gonzalez

flavicon
face
On Tue, 20 Oct 1998, Sean Breheny wrote:

>> > El problema es que el operador (suele ser una se–orita)  que
>> >extrae la bola, pronuncia el numero ante un microfono y enciende en un
>>
>> "suele" is what I couldn't understand, and couldn't find in a dictionary
(I
>  ^^^^^^^
>  'puede ser una senorita'
>   ^^^^^
>You probably got it right. A bout of dyslexia perhaps (d is near s and p
>is near l. There remains the task of swapping them in the same word).

>Peter

"suele" can be translated as "uses to be".

Calvin

More... (looser matching)
- Last day of these posts
- In 1998 , 1999 only
- Today
- New search...