| T O P I C R E V I E W |
| DVE |
Posted - 07/18/2025 : 11:39:57
Just got a new soviet (made in 1988) SI-22G GM tube by post.
It does not fit a bit into the case, however 
A first test with my DIY board shows ~85CPM for a background.
The plan is to put the tube outdoors using a 0.5-meter wire.
What settings are recommended to set? |
| 3 L A T E S T R E P L I E S (Newest First) |
| DVE |
Posted - 07/22/2025 : 11:21:03
The voltage is 390V, looks standard. A conversion rate is 792 to 1uSv/h (for M4011 it is 151) so it's about 5x more sensitive than a "standard" M4011.
I decided to use it with a Raspberry Pi, and upload the data to gmcmap with a software correction - no need to confuse people with a "red" point with high cpm values on a map :)
It's a weird decision that gmcmap uses CPM values as a default marker; uSv/h would be more universal. |
| EmfDev |
Posted - 07/21/2025 : 12:33:11
it is too long. what is the voltage requirements on that tube? |
| DVE |
Posted - 07/20/2025 : 02:56:58
I did some tests with the tube (for now, without GMC yet).
Its sensitivity is good - it detects a small uranium drinking glass from 10cm.
Test #1: Background fluctuation (~15 min)
Test #2: I placed 2 radioactive objects of different intensity at ~10cm from the tube (CPM values have some delay because of the sliding 60s window calculation). Even from such a distance, it's detectable.
It works well, but I'm still not sure if it makes sense to connect a SI-22G tube to GMC, or just keep the tube for separate experiments. |
