[time-nuts] Re: Z3801A Receiver Replacement

[Robert DiRosario]

Does this effect All Z3801As?
I have one of these:
http://www.realhamradio.com/GPS_Frequency_Standard.htm
I picked up a power supply and antenna for it but  haven't done anything 
with it yet.

 > I have a HP Z3801A with a dead GPS receiver.
Is it dead because of Week-Roll over limits or something else?

Robert


On 06/21/2021 11:54 PM, Art Sepin wrote:
> Hi Fred,
>
> 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.
>
> Apologies for the quasi-commercial intrusion!
>
> Art
>
>
> -----Original Message-----
> From: Frederick Bray <fwbray at mminternet.com>
> Sent: Monday, June 21, 2021 7:21 PM
> To: time-nuts at lists.febo.com
> Subject: [time-nuts] Z3801A Receiver Replacement
>
> I have a HP Z3801A with a dead GPS receiver.  I understand that it is possible to drop in an Oncore VP 8 channel receiver as a replacement -- not withstanding the fact that the Z3801A will only see six channels.
>
> I see that Motorola R5122U1154 8 channel receivers are available.  Does anyone know whether this will function in the Z3801A?  I'd like to get it working again.
>
> Thanks.
>
> Fred Bray, KE6CD
>
>
>
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