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New survey meter (kit) with Scintillation detector

Seoul_lasers

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I have been working on for the last month and a half building myself a survey meter kit for doing some Uranium hunting, general survey use and portable spectroscopy. I attained a Bicron M surveyor from a contact over at the Gamma spectroscopy yahoo groups with an LM-7232 end window GM tube.
This survey meter has been modded so that it can accept BNC connectors.

Benefits of this survey meter.
-Variable low ripple high voltage supply (up to 2Kv)
-CPM only analog read out (good for dose conversions of various tubes esp. scintillation probes)

- Circuit is 100% digital processing and has the ability to discriminate when using scintillation detectors. Meter is analog movement but can be adapted for digital scalers)

- 1x 9V cell (can be doubled for longer use)
- Very loud count ( has a classic clicker and a very annoying beep count rate function)
- SCA and scaler board add-on possible.
DIY also possible using a Pic18 processor. (plans available on Geiger counter enthusiasts forum)
- due to the low noise power supply, Gamma spectroscopy can be done off a
T bias with a 2Kv 10nF ceramic disk cap and a 2Kohm resistor to ground.
Pulses can then be fed into a sound card or to a DSO nano 201v2 (or similar)

In my kit I've got

Bicron M surveyor

2x Pomona 50ohm BNC cables

1x GEOS 210 LNC7311 GM detector
1x LNC7232
1x Irad Labs 1.5" Gamma Scintillation probe 1.2Kv (1125V running)

3X Radioactive check sources:

Uranium dioxide (NORM) sample 70 KCpm
80uCi Am241 (sealed) Low energy Gamma (~3.5% Np237)
Ra226 ~2uCi 3.75 mR/hr ~13,125-13,500CPM with a LND3711 Gamma/hard Beta eq.



Have a look at the pics posted.
 

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Sigurthr

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Very nice kit you've assembled! I'd love to see a pic of your portable MCA set up!
 

Seoul_lasers

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Jul 4, 2008
Messages
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Very nice kit you've assembled! I'd love to see a pic of your portable MCA set up!
I've also got ahold of the Theremino MCA pmt adapter, so I've actually got 2 projects on the go. The adapter has been constructed. Now it's the brains of the unit I have to construct/ figure out. I also need a NaI/Tl probe or equivalent.
LYSO is also a good scintillator material.
 




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