Hi When I want to tune an Rb, I just hook up to it with a terminal program and hack away at it. There's not a lot to the protocol.
Bob On Sep 18, 2013, at 6:49 PM, Bob Stewart <[email protected]> wrote: > Hi Bob, > > As always, thanks for your informed help. I had been reaching the same > conclusion, but needed unbiased confirmation. I think the RUBY4 software > does what I want? I'll look into it. > > Bob > > > > > >> ________________________________ >> From: Bob Camp <[email protected]> >> To: Discussion of precise time and frequency measurement >> <[email protected]> >> Sent: Wednesday, September 18, 2013 5:01 PM >> Subject: Re: [time-nuts] GPSDO vs Rb standard >> >> >> Hi >> >> One cycle of 10 MHz would be 100 ns. 100 ns per second would be 100 ppb. >> 100ns per 20 seconds would indeed be 5 ppb. >> >> Since the Rb is *stable* but not *accurate*, the real question is - how much >> does the 5 ppb change by? The Rb can't tell you if the GPSDO is correct. The >> best it can do is tell you if it changed. If you can demonstrate that the >> GPSDO is locked up, and that it's stable for many days, you can reasonably >> conclude that the GPSDO is accurate. >> >> I'd say the first step is to get the Rb tuned closer to the GPSDO. You >> should be looking for < 0.01 ppb changes. That's going to be tough with a 5 >> ppb offset. >> >> Bob >> >> On Sep 18, 2013, at 5:47 PM, Bob Stewart <[email protected]> wrote: >> >>> I hooked the Rb's 1PPS to the trigger input on my old Tek 455, 10MHz >>> GPSDO to Channel A, .05us trace, and turned the lights out so I could >>> see it. The 10MHz is marching right to left about 1 cycle every 20 >>> seconds. So, can I say that the Rb considers my GPSDO to be too fast by >>> about 5ppb? >>> >>> >>> Bob >>> _______________________________________________ >>> 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. _______________________________________________ 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.
