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

[Andrew Kalman]

I pinged Art at oeminfo at synergy-gps.com some time ago as they appear to
have announced a drop-in replacement for the Oncore modules, but I never
got a response. Dunno if they are still in business, etc.

I would like some for my HP Z3805As ...

He had previously posted to time-nuts:

" "*I apologize if the following smells overtly commercial; it's only
intended to *

*answer your questions and explain where we are in the process of producing GPS
replacement products for legacy timing instruments.*

*The 6 and 8 channel Motorola VP and 8 channel UT+ will not work as
replacements. Those products have also reached their 1024 Week-Roll Over
limits. The HP Z3801A and Z3805A products only respond to 6 channel commands
and produce 6 channel reply messages.

We have developed single-board clones for the Motorola VP and UT+ products, as
drop-in replacements, that are lower in cost than Synergy's 2-board Adaptor
Board products (Shooting for dropping to less than $190 if component prices
don't go even higher!). The SSR-VP can plug into the HP Z3801A and Z3805A
products.

A different part number SSR-VP designed to drop into HP 58503A and an SSR-UT+,
designed to drop into HP 58503B products, have also been completed but firmware
for those have yet to be tested in actual instruments. With the proper firmware
loads, the SSR Drop-In products should be candidates for upgrading many other
legacy timing instruments.

We had planned for the single board "Drop-In" products to be available near the
end of 2020 but COVID-19 changed things for us. We are now planning a small
production run to satisfy folks that have already been in touch with us but we
need to complete our boot-loader for firmware updates first. With current work
load, I'd estimate 90 - 120 days for HP Z3801A and Z3805A replacements. If you
are interested we can put you on our list."*

"

--Andrew

--------------------------------
Andrew E. Kalman, Ph.D.


On Fri, Apr 8, 2022 at 3:01 PM Dan Rae via time-nuts <
time-nuts at lists.febo.com> wrote:

> My faithful 3801, some 207 thousand hours old, has developed an
> occasional fault that I think must be down to the Motorola Oncore 6
> channel board and I wonder if there is an available unit that could
> replace this, or what the recommended substitute is?  eBay searches
> don't show any of the original ones.   I'd like to keep it going, it was
> the first GPSDO I got, and despite getting and building many others
> since, I'm stupidly fond of it.
>
> Thanks,
>
> Dan
>
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