Any Pancake GM Tubes used with MightyOhm Gieger kit?

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PiledHigherDeeper
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Any Pancake GM Tubes used with MightyOhm Gieger kit?

Post by PiledHigherDeeper »

Hi all - I have been considering (once I get the PCB to behave) using a LND 7317 SI-8 (CI-8), or SBT-11A pancake tube... I hear the 7317 is the best (http://www.lndinc.com/products/17/), and the SBT-11 (http://www.sovtube.com/en/x-ray-and-gei ... bt-11.html) is the best for the money at half the cost of an LND 7317... and the CI-8/SI-8 is also very good (http://www.sovtube.com/en/x-ray-and-gei ... ci-8b.html)

Anyone try - successfully or not - to use this ort of mica windowed-pancake tube? Any gotchyas or issues, recommendations, or keys to attaching? (I guess don't use long leads back to the counter, according to other threads)...

any help appreciated!
Paul, Flagstaff, AZ, NT3L
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mightyohm
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Re: Any Pancake GM Tubes used with MightyOhm Gieger kit?

Post by mightyohm »

I have not used a pancake tube with the kit. I have tested an LND-712- it worked fine and has a mica window.

LND 7317 is a 500V tube, it should work.
SBT-11A should work
SI-8B should work

Try them and report back!
PiledHigherDeeper
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Re: Any Pancake GM Tubes used with MightyOhm Gieger kit?

Post by PiledHigherDeeper »

Having gotten ahold of one of those Atomic Dave pancake mounting kits at eBay: http://www.ebay.com/itm/221258613381?ss ... 1439.l2649

I see it came with a 4.7-MOhm resistor for the anode... looking around it seems some kits don't need the resistor, some do - would it be correct to put this resistor at the Anode of my pancake in this kit? Or skip it?

Many thanks,
Paul
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mightyohm
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Re: Any Pancake GM Tubes used with MightyOhm Gieger kit?

Post by mightyohm »

The kit already includes a 4.7M anode resistor on the PCB (R2). You shouldn't need to add an additional external resistor, but it's likely that the kit will work with or without it.
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