Hi You will need to fine tune the firmware settings for that OCXO.
Bob On Jul 12, 2013, at 11:27 AM, Bob Stewart <[email protected]> wrote: > Hi Bob, > > OK, you got me: time as in about 120 minutes. =) It's mostly "+", with the > occasional "-" for about an hour or so. Then, it wavers back and forth > between "+" and "-", but the long term trend is still very slowly "+". So, > I guess the OCXO needs more time to "settle in"? My OCXO is a Trimble > 34310-T. > > As soon as I can get the serial port wiring done I'll be able to tell if it's > in "position hold" mode. I suspect it's not, as it doesn't have a battery > on-board. I did wind up mounting a Lithium 3V backup battery, using a holder > from an old motherboard. > > I'll have to look around to see if anyone has any software to graph the DAC > track for this board. > > Bob - AE6RV > > > > > >> ________________________________ >> From: Bob Camp <[email protected]> >> To: Discussion of precise time and frequency measurement >> <[email protected]> >> Sent: Friday, July 12, 2013 8:47 AM >> Subject: Re: [time-nuts] GPDSO is working >> >> >> Hi >> >> On Jul 11, 2013, at 11:59 PM, Bob Stewart <[email protected]> wrote: >> >>> After ham-fistedly breaking a few things, I've finally got my GPSDO >>> working. (does happy dance) Now that it's had some time to warm up >> >> Time as in minutes, or as in a couple of days? If you look at the plot in >> the QEX article, a day or so is the expected "warmup" period. >> >>> I see that it's started wandering around +/- a couple of counts from sample >>> to sample (16 seconds). >> >> If it's + *and* - then the gizmo is driving down the middle of the road. If >> it's always + or always - then it's likely not yet locked. >> >>> Is this because the UT+ is not set to timing mode? >> >> The UT needs to be in "position hold" mode with a proper (24 to 48 hour) >> survey on it's location for best performance. It should not be +/- 100 ns >> even without this. >> >> Is your VCXO a 10811? Does it have the same sensitivity as a 10811? If not, >> you may need (per the article) to make some firmware changes. >> >> Bob >> >>> Putting in an RS-232 (or USB) to TTL adapter, switchable between the UT+ >>> and the VE2ZAZ board, is pretty much next on my schedule. I've got an >>> adapter I made many years ago, but it's not suitable for mounting in the >>> box, and there's no simple way to hook it up to the UT+ at the moment. >>> >>> 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.
