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Zalkonian
Lithuania
1 Posts |
 Posted - 03/21/2024 : 08:46:09
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Hello. I wanted to find out which geiger counter would suit without needing to spend a lot of money and also learn if it's worth modifying the geiger tube.
Most important application for it would be the case of nuclear fallout or nuclear plant accident survival because my city Vilnius is close to Belarussian unsafe Astravec nuclear plant. If insane Putin decides to use nuclear weapons against NATO or even Ukraine there could be danger of nuclear fallout depending on wind direction.
I recently purchased a gmc-300e plus used geiger counter but decided to purchase another newer model like gmc-300s which is now well discounted and claimed to be more sensitive. But maybe the older gmc-300e plus still has advantages? In another forum I was told it's recommended to have two geiger counters for reading comparison.
Would gmc-300e plus or gmc-300s be sufficient or should I go for a more advanced, NRC certified device? Do I need a scintillation detector?
My other question is about tube modification. I have seen on Youtube that these Chinese glass tubes are being removed and replaced with soviet SBM-20 tubes. As I understand it, the larger tubes are more sensitive to radiation and the metal housing is more durable than the glass one, the glass ones can become more sensitive to light as well. Are the SBM-20 tubes the best for modding or are they just the most popular/have the best price quality ratio? SBM-20 tubes are abundant in post soviet countries including in my country. Maybe there are even tubes with mica or novel more durable material alpha pass windows? |
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| Reply #1
EmfDev
2159 Posts |
Posted - 03/21/2024 : 09:52:05
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Hi Zalkonian, those devices should be enough for your use case. The older version of 300s <= 1.14 is using a slightly longer tube so it is about 5% more sensitive. But now we are shipping 1.15 which are the same tube as the GMC-300e which is m4011/J321 tubes. The NRC certification is not needed for these counters as they are built in a similar way as the one that can be NRC certified, I.E. GMC-SE, GMC-800, etc.
We do not recommend modding your geiger counter. But if you are an expert, then our geiger counters are flexible enough to be compatible with other tubes. Even ones that can detect alpha. |
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| Reply #2
ullix
Germany
1115 Posts |
Posted - 03/22/2024 : 02:54:21
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Replacing M4011 glass tube with SBM20 is possible, but not recommended. Well discussed years ago: http://www.gqelectronicsllc.com/forum/topic.asp?TOPIC_ID=3654
But verify that your glass tubes aren't light sensitive. If they are the replacement might be helpful. The replacement can be made without any changes except mechanical.
Oh, by the way: the best survival measure might not be a Geiger counter but a battery operated radio! |
Edited by - ullix on 03/22/2024 02:56:49 |
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Dosimeter for fallout survival & tube modfication
