On 08/11/2013 05:18 AM, Mark C. Stephens wrote: > Okay this is what worked for me: > > 1. Removed power and antenna. > 2. apply power with no antenna. > 3. send :GPS:INIT:DATE 2007,08,11 > 4. plug antenna back in. > > For some reason if I used the correct date, the Z3815A warped back to 1993. > > But I am curious why did this happen today? GPS weeks begin on sundays. Today is first day of week 1753:
http://csrc.ucsd.edu/scripts/convertDate.cgi?time=2013+08+11 Going back 1024 days gives you week 729 day 0, which occurs on 1993 12 26: http://csrc.ucsd.edu/scripts/convertDate.cgi?time=1993+12+26 A simple way to compensate for the lack of bits is to assume wrapping occurs, so week numbers lower than som value actually lacks 1024 weeks. A trivial code like this fixes this: if (week < 729) week += 1024; Brilliant until you reach week 1753. I've seen this happen at 500 and 512. Cheers, Magnus > > > --marki > > -----Original Message----- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Mark C. Stephens > Sent: Sunday, 11 August 2013 1:06 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Warped back to 1993 > > Hal, I can't get it to take, I keep getting E-350 and the time does not > change. > Did you unplug the antenna or anything while you changed date? > > > > > > -----Original Message----- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Hal Murray > Sent: Sunday, 11 August 2013 12:54 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Warped back to 1993 > > > ma...@non-stop.com.au said: >> A Z3805A, a Z3815A and 58534A integrated timing antenna all think it's >> 26 Dec 1993. >> What happened?! _______________________________________________ > Is that off by 1024 weeks? (Looks close, but I haven't checked the details.) > > There is a week field in the GPS data stream. It's only 10 bits. > > I had that problem on a Z3801A. It did the right thing after I told it the > date. > :GPS:INIT:DATE 2011,12,26 > > > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.