[time-nuts] update on Z3801A repairs
paulswedb at gmail.com
Sun Feb 7 17:14:10 EST 2016
Congratulations Dave very good to hear its back in the land of the living.
Looking forward to the additional thread.
On Sun, Feb 7, 2016 at 12:37 PM, Artek Manuals <Manuals at artekmanuals.com>
> I had reported earlier that the power supply went south in my Z3801A ( and
> then the receiver) became a suspect as well
> In the final analysis I am not sure which went first the Z3801 supply or
> the external power supply I use to power the unit.Both have a clear
> failures.But both were down creating a little confusion at first about the
> The external supply has an adjustable current limit setting which is now
> nonadjustable at 150ma..have not dug into that one yet
> Once I figured out that my external supply was bust I switched to another
> supply I have here in the lab to find that the internal Z3801A supply still
> had a problem. As I noted in an earlier post there is a "pre processing"
> section which I am told was really a over-voltage protection section and
> the DC-DC converter section. The problem fortunately is in the the voltage
> protection section and I have not bothered to run it down.Instead I have
> reverted for now to bypassing the front end of the supply and am now
> feeding 36V directly into the DC/DC converter an easy thing to do at the
> output of L1 with a simple and convenient trace cut. SO not sure which
> supply took out which supply but for now the unit is powered on another
> supply .with the overkil / over-voltage circuit bypassed
> A few days after I started things back up the receiver began to error out.
> At first it would error after 8 hours, then after an hour and now it only
> lasts about 20 minutes. Again no obvious suspects on the receiver board in
> terms of smoked caps etc. At that point another list member who has a cache
> of Motorola Oncore boards that I knew well from another list offered to
> send me a replacement Moto receiver, which turned out to be plug and play
> compatible. the new-used receiver fixed the problem in spades so we are
> back with a working Z3801A. I will cover the receiver update from an Moto
> 6CH Oncore to a 8CH VP Oncore in a separate post
> Manuals at ArtekManuals.com
> This email has been checked for viruses by Avast antivirus software.
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to
> and follow the instructions there.
More information about the time-nuts