[time-nuts] Z3801A holdover

[J. L. Trantham]

Joe,

I recently had a problem with my Z3816A where it reported an erroneous date, 2035 IIRC.  However, the time was accurate.

It was only tracking 4 sats and the signal strengths were low.  My TBolt was tracking 8 sats with good signal strength.  My antenna feeds a Symmetricom 58536A 4 way splitter and that feeds the receivers.

I 'rebooted' the unit by turning off power, leaving it overnight then turned it on.  Same thing.

I then removed and replaced the 'battery backup batteries' (they tested good) that I had installed and restarted it.  It never found itself.  I then gave it the Lat/Long and it found itself, with the correct time but with only 4 sats and with low signal strength.

I then replaced the GPS receiver and now all is well.  It found itself, 8 sats, good signal strength, correct date and time, as compared to the TBolt.

So, the GPS receiver might be on the list for your problem.

Does anyone know anything about how to repair these receivers?

Thanks.

Joe
WB4BPP



-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces at febo.com] On Behalf Of Joseph Gray
Sent: Wednesday, February 24, 2016 10:37 PM
To: Discussion of precise time and frequency measurement
Subject: [Bulk] [time-nuts] Z3801A holdover

I just took a look at my Z3801A that has been in holdover for some time. I have been too busy to do anything about it until now.

Before looking at the receiver stats just now, my first guess was that the Oncore GPS board went bad. However, I see that it is currently tracking 4 sats. I also see that the 1pps is invalid. Does this still point to a failed Oncore board?

Attached is a screenshot showing the receiver stats.

I will open this thing up over the weekend to check voltages and such.
Until then, any tips on where to look are appreciated.

Joe Gray
W5JG