Arduino based GM counters

[Richard Hull]

I have been toying with the arduino and linking it to my rather large stash of 5979 GM tubes. These tubes are 6 inches long and an inch in diameter. They have a mica window meaning they detect alpha, beta and gamma radiation, which is really nice.

I have merged them into a rather labor intensive "ray gun" style counter of two varieties. (see images below)

One has a reflective type 4X20 LCD display and the other is identical, but uses a 2X16 "Backlit" display.
Both types give 4 lines of data
1. Total counts since reset (running count)
2. Current CPM (udated every ten seconds)
3. Current Dose rate in mrem/hr (updated every 10 seconds)
4. Current absorbed dose at GM tube face in mrem (updated every ten seconds)

They both use a standard 9 volt transistor radio battery. The handles are removable via a thumbscrew allowing the counter to be mounted on a tripod or camera copy stand via its 1/4 X 20 female thread base. (gotta' stain those wood handles!)

I have both at $200.00 each for sale at hamfests and mineral shows where I sell trinitite and U ore. I have sold 3 already and am already tired of all the machine work, drilling and tapping etc. The circuit boards are from Express PCB. I used their free software to design them and they made them up in no time. I was very pleased with them.

I thought you might like to see my results.

Richard Hull

[Andrew Robinson]

Looks pretty cool Richard! Looking forward to seeing them in person this October.

By the way, kudos for using ExpressPCB. I LOVE ExpressPCB (Although I dont love what they recently did to their website...)! I have been using them for years now. Good to see someone else out there using a somewhat small esoteric total PCB solution. While there custom software is not exactly Eagle, it sure makes the entire process streamlined. LOVE IT!

[Bob Reite]

I also have used Express PCB. A one stop solution for circuit boards.

[Jerry Biehler]

ExpressPCB is fine for when you need something real quick but if you can wait a week or two OSHPark is the way to go. Very good boards for very good prices. Two layer, gold plated, purple conformal, silks both sides, 7 mil traces. You get three boards for $5 per square inch.

[Richard Hull]

Update...

I no longer use the long mica windowed tube as it forces an increased price that is a "bridge too far" for many.
I now use the Russian STS-5 GM tube in all counters and the new models run around $100 and sell right along to mostly mineral collectors and prepers.
The latest and last revision PCB for all my counters support many display options.
A few images below

Richard Hull