After about three hours: https://dl.dropboxusercontent.com/u/19599147/Z3801A%203hr.png
Ignore the graph discontinuity at the beginning. I had to power cycle to change to UTC. Joe Gray W5JG On Sun, May 1, 2016 at 1:30 AM, Joseph Gray <jg...@zianet.com> wrote: > In past discussions about replacing a 6-channel Oncore in a Z3801A > with an 8-channel VP Oncore, some claimed that the VP had to first be > put into 6-channel mode, others indicated this was not necessary. > Earlier tonight, I put a VP (still in 8-channel mode) into my > malfunctioning Z3801A. Monitoring with Z38xx, I see no signs that this > is a problem. Even the logs look clean. > > In reading the VP documentation, I saw that there were several > 6-channel commands, along with similar 8-channel commands. That is why > I thought I'd try using the VP without setting it to 6-channel mode. > It was an experiment that seems to have succeeded. > > I don't want to jinx things, but so far, my formerly flaky Z3801A is > working normally, after replacing the GPS module. The self survey > finished in two hours (about 25 minutes ago). The EFC and PPS TI/s > graphs are no longer going wild. > > I'm going to monitor this for quite a while before I call it fixed. > Then it's on to repairing the Z3801A that I traded for. > > In addition to replacing the GPS module, I also replaced three caps on > the power supply board. On initial inspection, C108 and C110 had a > faint white ring around them, on the PCB, as though they had out > gassed. There was also some corrosion on pin TP104, which sits between > C108 and C110. The caps checked fine with my LCR meter, but I thought > I'd replace them while I had things apart. I also replaced C111, which > is nearby. When I removed the caps, there was no corrosion on the PCB. > > When I inspected the other Z3801A which is awaiting repair, I saw the > same faint white rings around C108 and C110. There was no corrosion on > TP104, however. I will replace those caps as well, when I get to it. > > > Joe Gray > W5JG _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.