I apologize for a question that's probably been asked a zillion times before but the Z3801 that I've had for years (but not in service) won't lock on to satellites anymore and I'm looking for any suggestions as to how to troubleshoot it. I know the antenna works as I also have a Leo Bodnar GPSDO that it works fine on and when connected to the Z3801 there is voltage across the antenna. It seems to power up OK but just sits with the Holdover LED lit,  which I assume means it's not hearing any satellites. Some time ago the 5V power supply module failed, and I wired in a different one, which is putting out 5.0 volts so that's not the problem. My understanding is the unit should lock on to satellites and work without any serial commands.   I converted the port from RS-422 to regular serial but the old PC with a real serial port I used to use is long gone - so I'd appreciate knowing if there is a reason to try to restore the serial connection, and if so what software to use.    It's probably wishful thinking to hope for any kind of diagnostic software - but maybe? Thanks for any ideas as to how to identify the problem, 73, Bob W9RAN

Hi Simple answer is to grab a USB to serial adapter and fire up Lady Heather: http://www.ke5fx.com/heather/readme.htm Depending on what you did in converting to RS-232 from RS-422, you might need to fiddle a few of the control lines. Bob > On Apr 27, 2024, at 1:09 PM, Robert Nickels via time-nuts <time-nuts@lists.febo.com> wrote: > > I apologize for a question that's probably been asked a zillion times before but the Z3801 that I've had for years (but not in service) won't lock on to satellites anymore and I'm looking for any suggestions as to how to troubleshoot it. > > I know the antenna works as I also have a Leo Bodnar GPSDO that it works fine on and when connected to the Z3801 there is voltage across the antenna. It seems to power up OK but just sits with the Holdover LED lit, which I assume means it's not hearing any satellites. > > Some time ago the 5V power supply module failed, and I wired in a different one, which is putting out 5.0 volts so that's not the problem. > > My understanding is the unit should lock on to satellites and work without any serial commands. I converted the port from RS-422 to regular serial but the old PC with a real serial port I used to use is long gone - so I'd appreciate knowing if there is a reason to try to restore the serial connection, and if so what software to use. It's probably wishful thinking to hope for any kind of diagnostic software - but maybe? > > Thanks for any ideas as to how to identify the problem, > > 73, Bob W9RAN > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com