John, I had a look in the February 1973 5061A manual (serial prefix 1248). There is a small note on Figure 8-5 wiring diagram stating different frequency offsets R6 OPTION 004, 12 M 2E-12, 10M 2 to 3E-12 5M 3 to 4E-12 .... If you need a scan of this page, let me know. Best regards Hubert
-----Urspr�ngliche Nachricht----- Von: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Im Auftrag von Tom Van Baak Gesendet: Mittwoch, 6. April 2005 16:37 An: Discussion of precise time and frequency measurement Betreff: Re: [time-nuts] 5061 Cs frequency shift with long time constant? > Following up on Brian's comment yesterday, I'm investigating sources for > very low leakage caps. If I find some, I'll let the group know, and if > there's a minimum purchase quantity that's reasonable, I may just buy a > bunch and make them available to the group here. > > John John, Before you think of replacing the special one that HP chose you might want to measure the leakage you have. Do you have a matching schematic for your A9 board? There are a couple of handy test points where you can introduce an artificial load across the cap to confirm the amount of frequency offset vs. the amount of leakage. One of mine shows a 100k in series with the cap becoming 12M in LTC mode. So shunt the cap with something like 5M or 10M and see what happens to your frequency. /tvb _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
