[time-nuts] HP Z3817A Reverse Engineering
David Hooke
dhooke at gmail.com
Sun Oct 27 19:26:33 UTC 2013
Hi Ed,
My E1938 also came from a very battered STLN4096A from the same source,
and I might also try to get the other boards functional. Could you share
the details of the GPS connections, and which GPS receiver you used?
Cheers,
david
> I recently purchased a Motorola STLN4096A with the HP E1938A
> oscillator. I bought it for the oscillator only.
>
> Then I got intrigued by the HP Z3817A GPSDO that's included. I've
> reverse engineered most of it and I've got it running. The 1 PPS is
> really good ( 1000 measurements, Std. Dev. of <200 ps, min to max
> range of <1.5 ns) and the HUP is very slowly dropping (currently at 13
> us after ~1.5 days) as the oscillator works out the kinks after it's
> long sleep. It's dropping much slower than my Z3801A did when I first
> turned it on.
>
> There's one input that I haven't been able to figure out. I've got
> data in and 1 PPS in from the GPS receiver. Everything seems to be
> working so I'm at a loss what that the other input could be for.
> There are no clues to it's function because it appears to go into one
> of the Xilinx chips.
>
> Does anyone have any more info on the unit? Has anyone figured out
> the other input?
>
> I have searched the net and the archives. There's very little info or
> discussion on this unit.
>
> Ed
>
>
More information about the Time-nuts_lists.febo.com
mailing list