Gradual count increase at FSM19

Looking back over the last few months, there seems to have been a gradual increase in counts on my counter. The probe hasn't been moved, and there have been no other changes. We have had a very lengthy period of rain locally, most days since November last year. Any ideas? Ther have also been some very odd readings. One problem we have here is a pretty ropey internet connection (G4 in a pretty remote location), we get very low connection rates and frequent outages. When We have an outage I do try to remember to reset everything.

 

I tried swapping tubes, last night, and checked the ht, didn't make any difference. I'm going to try two other things, one is to move my sources a couple of metres further away, and also check with a couple of other counters.
Interesting, I tried another counter also with an SBM20, it is also reading significantly higher periodically. It's not a power supply issue, which was also a thought as the second counter is battery powered.


 

Maybe encase them in some lead and check if the readings are almost 0. If not there might be something wrong with your hardware.

I think I may have found the solution, a noisy power supply, but I'll leave my counter online and see what happens. FIXED!The chinesium smpsu was noisy, obviously this had been getting worse over time. I replaced it with an old fashioned linear , transformer based supply.

Still getting a random spike or two. Maybe due to the local mains supply being rather nasty. I've been comparing what has been happening in my home when the spikes happened today, they all appear to be related to mains power switching related to cooking, and me using my arc welder. So I'm going to have a good look at my power supplies. Being in a rural area means our power lines are pretty noisy.