voltage problem Geiger Counter
Posted: Sun Jun 17, 2018 2:05 pm
Hello,
I purchased a kit from Adafruit with SMB-20 and case. It seems to be picking up random radiation but the HV_Adjust doesn't seem to be doing anything--it works the same on both ends of the pot. I don't have a source to test it other than bananas which don't seem to do much.
Here are my voltage readings from new batteries (3.054 volts) Using a Fluke 87 III
U1 pin
1: 0
2: 1.59
3: 1.18
4: 2.91
5: 2.03
6: 0
7: .562
8: 3.054
Remove U1
4: .04
TP1: 2.95 (this seems off but maybe I'm not measuring it correctly--(ground to TP1)
TP2 to ground: adjusting HV with pot I get 167 -> 310 volts (no resistor being used)
Serial out from FTDI Friend:
mightyohm.com Geiger Counter 1.00
http://mightyohm.com/geiger
CPS, 0, CPM, 0, uSv/hr, 0.00, SLOW
CPS, 1, CPM, 1, uSv/hr, 0.00, SLOW
CPS, 0, CPM, 1, uSv/hr, 0.00, SLOW
CPS, 1, CPM, 2, uSv/hr, 0.01, SLOW
CPS, 0, CPM, 2, uSv/hr, 0.01, SLOW
CPS, 0, CPM, 2, uSv/hr, 0.01, SLOW
CPS, 0, CPM, 2, uSv/hr, 0.01, SLOW
CPS, 1, CPM, 3, uSv/hr, 0.01, SLOW
CPS, 1, CPM, 4, uSv/hr, 0.02, SLOW
CPS, 0, CPM, 4, uSv/hr, 0.02, SLOW
CPS, 0, CPM, 4, uSv/hr, 0.02, SLOW
CPS, 1, CPM, 5, uSv/hr, 0.02, SLOW
CPS, 0, CPM, 5, uSv/hr, 0.02, SLOW
CPS, 2, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 1, CPM, 8, uSv/hr, 0.04, SLOW
CPS, 0, CPM, 8, uSv/hr, 0.04, SLOW
CPS, 1, CPM, 9, uSv/hr, 0.05, SLOW
CPS, 3, CPM, 12, uSv/hr, 0.06, SLOW
CPS, 0, CPM, 12, uSv/hr, 0.06, SLOW
CPS, 0, CPM, 12, uSv/hr, 0.06, SLOW
CPS, 0, CPM, 12, uSv/hr, 0.06, SLOW
CPS, 0, CPM, 12, uSv/hr, 0.06, SLOW
CPS, 0, CPM, 12, uSv/hr, 0.06, SLOW
CPS, 1, CPM, 13, uSv/hr, 0.07, SLOW
Could anyone comment on this? Maybe it's ok but I want to be sure. Thanks in advance.
Bob
I purchased a kit from Adafruit with SMB-20 and case. It seems to be picking up random radiation but the HV_Adjust doesn't seem to be doing anything--it works the same on both ends of the pot. I don't have a source to test it other than bananas which don't seem to do much.
Here are my voltage readings from new batteries (3.054 volts) Using a Fluke 87 III
U1 pin
1: 0
2: 1.59
3: 1.18
4: 2.91
5: 2.03
6: 0
7: .562
8: 3.054
Remove U1
4: .04
TP1: 2.95 (this seems off but maybe I'm not measuring it correctly--(ground to TP1)
TP2 to ground: adjusting HV with pot I get 167 -> 310 volts (no resistor being used)
Serial out from FTDI Friend:
mightyohm.com Geiger Counter 1.00
http://mightyohm.com/geiger
CPS, 0, CPM, 0, uSv/hr, 0.00, SLOW
CPS, 1, CPM, 1, uSv/hr, 0.00, SLOW
CPS, 0, CPM, 1, uSv/hr, 0.00, SLOW
CPS, 1, CPM, 2, uSv/hr, 0.01, SLOW
CPS, 0, CPM, 2, uSv/hr, 0.01, SLOW
CPS, 0, CPM, 2, uSv/hr, 0.01, SLOW
CPS, 0, CPM, 2, uSv/hr, 0.01, SLOW
CPS, 1, CPM, 3, uSv/hr, 0.01, SLOW
CPS, 1, CPM, 4, uSv/hr, 0.02, SLOW
CPS, 0, CPM, 4, uSv/hr, 0.02, SLOW
CPS, 0, CPM, 4, uSv/hr, 0.02, SLOW
CPS, 1, CPM, 5, uSv/hr, 0.02, SLOW
CPS, 0, CPM, 5, uSv/hr, 0.02, SLOW
CPS, 2, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 0, CPM, 7, uSv/hr, 0.03, SLOW
CPS, 1, CPM, 8, uSv/hr, 0.04, SLOW
CPS, 0, CPM, 8, uSv/hr, 0.04, SLOW
CPS, 1, CPM, 9, uSv/hr, 0.05, SLOW
CPS, 3, CPM, 12, uSv/hr, 0.06, SLOW
CPS, 0, CPM, 12, uSv/hr, 0.06, SLOW
CPS, 0, CPM, 12, uSv/hr, 0.06, SLOW
CPS, 0, CPM, 12, uSv/hr, 0.06, SLOW
CPS, 0, CPM, 12, uSv/hr, 0.06, SLOW
CPS, 0, CPM, 12, uSv/hr, 0.06, SLOW
CPS, 1, CPM, 13, uSv/hr, 0.07, SLOW
Could anyone comment on this? Maybe it's ok but I want to be sure. Thanks in advance.
Bob