Morning update. The voltage on pin 4 is now -1.082 VDC and the HV is up to 2118 VDC. The +3500 V power supply is not 'hot' and therefore, there appears to be progress.
Thanks for all the suggestions. I like the idea of the multiplier. I've known about these but never knew they had a name and had forgotten about that approach. All I have to do now is o see if I have a suitable transformer in my junk pile. We'll see what happens first, the tube pumps down or I get around to building the power supply. Joe -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of J. L. Trantham Sent: Saturday, January 16, 2010 9:32 PM To: 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] 4 KV Power Supply Recommendations Sorry, TIA. I was monitoring pin 4, not pin 3. Pin 3 is -1.129 VDC which would imply a current of 112.9 uA. I will watch overnight and see what happens. Any thoughts appreciated. Joe -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of J. L. Trantham Sent: Saturday, January 16, 2010 9:02 PM To: [email protected] Subject: [time-nuts] 4 KV Power Supply Recommendations I have a 5061A That I am trying to bring on line and it pegs the Ion Pump I meter reading. Measuring the voltage at pin 3 of the +3500V power supply, I get -0.275 VDC. This is across a 10K resistor and suggests that CS tube current is 27.5 uA. The voltage from the power supply with the tube connected is 2050 VDC and around 3100 VDC with the tube disconnected. It is recommended to connect the tube to an external 3500 VDC supply capable of 5 mA and let it run to see if the current will come down. Having watched the voltage on pin 3 during the day, it has come down to -0.269 VDC and the voltage with the tube connected has gone up to around 2075 VDC. Any thoughts on a source for an external HV power supply for this application? Any thoughts on whether to just let it sit for a week or two to see if it 'pumps down'? Any thoughts on other things to try? Thanks, Joe _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
