Hi A lot of “dead” Z3801’s have a blown fuse link input on the power supply. I’d check that first.
Bob > On Mar 16, 2016, at 9:56 PM, Joseph Gray <[email protected]> wrote: > > Thanks to all for the comments. I recently traded for another Z3801A > that I was told didn't work. I don't know what is wrong with it, as I > haven't had time to put it on the bench yet. I understand that the > OCXO is putting out a decent 10 MHz, so perhaps it also has a bad > Oncore. > > Joe Gray > W5JG > > > On Wed, Mar 16, 2016 at 3:56 PM, Artek Manuals <[email protected]> > wrote: >> Joe >> >> The newer Motorola VP-Oncore receivers are known to be an improved design >> over the original Oncores that came with the Z3801A's . >> >> I have recently done some side by side comparison's with two z3801A's on >> the same antenna the newer Vp-Oncore's ran SS numbers 15-30 points higher on >> the same bird than the older receiver. In all fairness the older receiver is >> on its last legs (see last paragraph below) >> >> I also found out that there are two versions of the newer VP-Oncore. These >> can be distinguished by the antenna connector, One version has a right-angle >> chassis mounted connector like the original 6CH Oncore, the 2nd version has >> a straight on antenna connector. This 2nd version while they will work in a >> Z3801A, have an interference fit problem with a an IC on the board below >> when the antenna cable is plugged in and you can't tighten down all the >> receiver board mounting screws. I am told that the straight on version fits >> the Z3816A with no problem. I have not verified this since I don't have a >> Z3816. I have no info on the other Z38xx models and the fit of the later >> VP-Oncore >> >> The older 6ch Oncore receivers receivers are beginning to die apparently. I >> have had one fail here a few months ago and recently acquired a 2nd Z3801A >> that is displaying similar symptoms to the first failure in that the >> receiver just stops working after a few hours...over time the symptom are >> the receiver drops out for no apparent reason then revives if the unit is >> powered off for a while. Over time the time to receiver drop out gets >> shorter and shorter after each successive power cycle, I have one receiver >> that will now fail within 20 minutes predictably. >> >> Dave >> NR1DX >> >> >> >> >> On 3/16/2016 7:03 AM, Joseph Gray wrote: >>> >>> I understand that the Oncore GPS in the Lucent units is a newer module >>> that tracks eight satellites, vs the older Oncore in the Z3801A that >>> only tracks six satellites. >>> >>> I decided to do a re-survey with my Z3801A that has been in holdover >>> for some time, just as a test. Watching the status screens from both >>> GPSDOs, both are seeing the same number of satellites, however, the >>> Z3801A is consistently locking to 3-4 fewer than the Lucent. >>> >>> This begs the question, is the older Oncore module that deaf, or is >>> mine defective. BTW, same antenna on a 4-port splitter, same elevation >>> mask. >>> >>> Joe Gray >>> W5JG >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> >> >> -- >> Dave >> [email protected] >> www.ArtekManuals.com >> >> --- >> This email has been checked for viruses by Avast antivirus software. >> https://www.avast.com/antivirus >> >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
