The DMAD works with the MightyOhm Geiger Counter

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will1384
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Joined: Sat Nov 26, 2011 8:17 am

The DMAD works with the MightyOhm Geiger Counter

Post by will1384 »

I ordered the "DMAD Expansion Module for Geiger Counters" from imagesco.com, and yes it works
with the MightyOhm Geiger Counter, a few things,

(1) You need fresh batteries in the Geiger Counter, the DMAD is looking for a +5V pulse, the
MightyOhm Geiger Counter is only putting out a +3V pulse, with the batteries in the Geiger
Counter around 2.5v the DMAD was not working 100%, it did work, but seem to miss some counts
and the random number generator sometimes fails to work.

(2) Only wire up (Pulse) and (GND) between the DMAD and the MightyOhm Geiger Counter.

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mightyohm
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Re: The DMAD works with the MightyOhm Geiger Counter

Post by mightyohm »

Excellent! Thanks for sharing your results!

will1384
Posts: 6
Joined: Sat Nov 26, 2011 8:17 am

Re: The DMAD works with the MightyOhm Geiger Counter

Post by will1384 »

I may add a "Logic Level Converter" from sparkfun.com, if it works, it should fix the low battery problem
when using the MightyOhm Geiger Counter with the DMAD.

will1384
Posts: 6
Joined: Sat Nov 26, 2011 8:17 am

Re: The DMAD works with the MightyOhm Geiger Counter

Post by will1384 »

I just finished the random number generator box I was making, I did use the "Logic Level Converter" from sparkfun.com
but dont know yet if its helping or not, I would have to test with weak batteries.

Partial list of parts used:

Instrument case, 7.9"x6.3"x2.5" ----------- Part Number: 18869
Logic Level Converter ------------------- Part Number: BOB-08745
Panel mount 50-Ohm BNC Connector ------ Part Number: 355120
50-Ohm BNC Coax cable 24 inch ---------- Part Number: 256743
Digital Meter Adapter Kit ---------------- Part Number: DMAD-03


Image

I reversed the speaker and the led so that they were mounted on the underside of the board, I also removed the
2-AAA battery holder and replaced with an 2-AA battery holder, and removed the Geiger-Muller clips so that the
tube could be mounted externally.

Image
Image
Image

I put the Geiger-Muller tube into some PVC pipe, I used some electrical tape to cover were the metal clips are attached to
the Geiger-Muller tube, and used cotton to fill the PVC pipe to hold the Geiger-Muller steady.

One thing that worries me, what happens if the random number generator box is run without the probe attached :?:

will1384
Posts: 6
Joined: Sat Nov 26, 2011 8:17 am

Re: The DMAD works with the MightyOhm Geiger Counter

Post by will1384 »

I wondered about using the Random numbers on the computer from the DMAD,
what I found is that most terminal emulators will display something unreadable
from the DMAD when in random number mode, if you find a terminal emulator that
can view and save the data has HEX, that file then then be converted to decimal.

I am looking into a better way, but here is how I am doing it now.

I use a program called "Terminal", I set it to "HEX" and then press "StartLog",
I let it run for how ever long I want, and then press "StopLog", I open that
file in a program called "Replace Pioneer" and click on "Replace" then
"Replace by template" then "Binary/Octet/Decimal/Hex Conversion" then
"Convert text from Hex to Decimal", you then select your "Input file" and
"Output File" and click on "Replace"

Here is a sample

Before conversion

Terminal log file
Date: 12/18/2011 - 2:52:55 PM
-----------------------------------------------
35 3A 04 10 1E 0E 12 04 10 08 16 0D 16 1C 3A 06
19 38 0D 08 10 05 25 39 19 21 2C 06 2C 0B 18 08
27 06 38 01 22 3C 3B 0F 1C 1A 1A 2D 25 22 19 17
05 1F 27 16 04 36 13 10 23 09 0C 05 18 35 07 26
08 1C 08 01 1B 0B 05 32 1B 17 34 01 05 35 10 1F
0E 05 1D 1F 19 03 0F 04 0C 3B 06 17 09 08 06 17
0C 1C 01 0F 0F 07 20 28 3C 31 0D 04 17 3D 2E 17
24 26 0A 05 0B 04 04 0B 0E 05 16 2F 24 18 0A 1A
30 35 14 09 02 2A 07 17 19 02 08 0A 2E 05 01 17
2D 12 1E 13 1D 03 01 32 32 0F 15 0A 1B 1B 26 18
33 1B 09 0C 0B 06 17 3F 18 3C 3A 3A 3C 0F 1E 20
08 21 33 2B 01 0E 11 3F 02 2E 1B 3E 26 0D 21 0C
05 22 03 2B 36 21 1B 20 07 06 3F 16 24 30 09 07
1D 15 11 37 21 02 2C 0C 08 07 0F 27 14 25 07 02
19 0A 0D 04 04 1B 37 1E 11
-----------------------------------------------
Date: 12/18/2011 - 2:53:32 PM
End log file

After Conversion

Terminal log file
Date: 12/18/2011 - 2:52:55 PM
-----------------------------------------------
53 58 4 16 30 14 18 4 16 8 22 13 22 28 58 6
25 56 13 8 16 5 37 57 25 33 44 6 44 11 24 8
39 6 56 1 34 60 59 15 28 26 26 45 37 34 25 23
5 31 39 22 4 54 19 16 35 9 12 5 24 53 7 38
8 28 8 1 27 11 5 50 27 23 52 1 5 53 16 31
14 5 29 31 25 3 15 4 12 59 6 23 9 8 6 23
12 28 1 15 15 7 32 40 60 49 13 4 23 61 46 23
36 38 10 5 11 4 4 11 14 5 22 47 36 24 10 26
48 53 20 9 2 42 7 23 25 2 8 10 46 5 1 23
45 18 30 19 29 3 1 50 50 15 21 10 27 27 38 24
51 27 9 12 11 6 23 63 24 60 58 58 60 15 30 32
8 33 51 43 1 14 17 63 2 46 27 62 38 13 33 12
5 34 3 43 54 33 27 32 7 6 63 22 36 48 9 7
29 21 17 55 33 2 44 12 8 7 15 39 20 37 7 2
25 10 13 4 4 27 55 30 17
-----------------------------------------------
Date: 12/18/2011 - 2:53:32 PM
End log file

I had the DMAD set to make random numbers from 1 to 64, and
was using a smoke detector as my radiation source.

BTW Here are the links to the programs I used.

Terminal
http://sites.google.com/site/terminalbpp/

Replace Pioneer
http://www.mind-pioneer.com/

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mightyohm
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Re: The DMAD works with the MightyOhm Geiger Counter

Post by mightyohm »

Thanks for sharing this!

RealTerm will display data in a variety of formats, including HEX.
http://realterm.sourceforge.net/

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