[time-nuts] Trak 8810 Station Clock

[Chris Quayle]

Hi,

Bought one of the above gps clocks at a radio rally last
Sunday. Looked ok on the outside, but severe corrosion
from a leaked backup battery inside. Cleaned all that up,
replaced some caps and a few other parts on the psu board
and now at least partially working. All the menus seem to
work, no signal or power failures, leds blinking 1pps on
the main board and all rear panel outputs seem ok.

Problem is that the gps engine fails to initialise in post.
Can't find any reference for this model on the web.
Did find an 8820 manual, but that has a different mainboard
and the serial port command set doesn't work on the 8810,
though characters are echo'd.

This looks like very early gps module and no info on the
web for it. Read one page that suggests that this module
might be similar to the Magnavox MX4200 and perhaps a
connection to Truetime ?, but no other info found.

The board says "Magnavox GPS Engine", with a part number
label 900578-803-3. Data codes on the devices are 1990-1992,
so must be a very early model. Question is, are there any
later gps modules compatable with this device in terms of
command set, or perhaps a known working board for sale, or
a manual somewhere ?. There's a neat output board that takes
a 10 Mz input, to provide 4 of each 1, 5  and 10Mhz sine
wave outputs on the back panel, useful in itself, but it
would be good to have this working, to add to the collection.

Thanks,

Chris