[time-nuts] Re: Z3801A GPS Rx board substitute?

[Andrew Kalman]

Hmmm ... I have four Z3805As, and one of them with 84k hours doesn't work
any more ... in its case, LH reports no az/el/signal strength for ANY
channels, i.e. it is not getting anything from the B1121P1114 Oncore
receiver. But it throws no errors. I presume there is some problem in the
front-end. +5Vdc does show up on the antenna connector ...

I tested this same unit with a later, same-form-factor R5122U1154 Oncore
8-channel NOS Oncore unit I bought off eBay, and in that case, the Z3805A
reported GPS errors (because the R5122U1154  8-channel units is not true
drop-in compatible with the B1121P1114 6-channel OnCores, apparently -- I
think the new one talks a different protocol).

TL, DR: in my particular case, it appears that the front-end of my original
6-channel B1121P1114 OnCore GPS receiver has gone bad, with all
communications between the receiver and the rest of the Z3805A still
working fine.

Sorry, I don't seem to have a LH screen cap of the problem.

Hence my interest in Synergy's drop-in upgrade for the B1121P1114 6-channel
OnCore GPS receiver in the Z3805A.

-- Andrew

On Sat, Apr 9, 2022 at 11:12 AM Dan Rae via time-nuts <
time-nuts at lists.febo.com> wrote:

> I have attached a LH screen shot which includes a two hour long holdover
> of the 3801A in question.  Needless to say none of the six other GPSDOs
> connected to the same antenna / distribution amp were affected.  It is
> certainly not an oven failure.
>
> I'll be waiting for Synergy...
>
> Dan
>
> ac6ao
>
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