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Randoid
USA
1 Posts |
 Posted - 01/29/2025 : 18:56:58
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I had a reading today of 150000 CPM near a "diagnostic" I-131 source before I ingested it. Near me it was 60000 CPM for a while. I can expect a much higher dose if treated. I see the alarm limit is 999999. Is this the maximum CPM the GMC-800 can read?
If saturated, any advice on calculating the CPM? For example, measure at two non-saturated distances and do some 1/r-squared magic and assume the source has a radius of 1 foot? |
The HotOne |
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| Reply #1
EmfDev
2292 Posts |
Posted - 01/30/2025 : 11:21:44
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| It is not saturated at 999999, it can read higher if possible. |
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| Reply #2
GTS
USA
39 Posts |
Posted - 02/16/2025 : 14:41:59
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GMC sales says the Maximum CPM is:
Item MAX cpm GM tube type
500 999,999 Hotdog
500+ 999,999 Hotdog
800 299,999 Hotdog
600 982,980 Small Pancake?
600+ 999,999 Pancake
For comparison, Radeye sales says:
B20 600,000 Pancake
B20ER 30,000,000 Pancake
And SEI Says:
Ranger 350,000 Pancake
All to be taken with a grain of salt.
If you watch Radioactive Drew, video "Which Geiger Counter Could Save Your Life From Radiation Exposure?", the 600+ "clicker" QUITS at greater than 180,000 CPM but still measured the rock at 340,000 CPM. FYI, This problem was pointed out several months ago right here on this forum. This is kind of disappointing but for the price, can you really complain?
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Edited by - GTS on 02/16/2025 15:14:50 |
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GMC-800 Maximum CPM?
