[time-nuts] Questions on a salvaged GPS disciplined 10 Mhz osc

[n3izn at aol.com]

Hello new to the list and I have some questions about a GPS disciplined(?) 10 Mhz oscillator I acquired. Wondering if you guys could help. I was referred to this list from the microwave group.
 
I’m cleaning out a site that was vandalized when I came across a piece of equipment that had a GPS in, 10 Mhz and 1 PPS out. Along with some other functions. So I saved it from the dumpster.
 
I power it up and hook it to an external GPS antenna. Yes I have 5 volts on the line to power the antenna. After several hours it never locked up. I’ve seen these units in other sites and now how they react when powered back up. The unit is noisy and draws a lot of juice, about 6 amps @ -48VDC Since I don’t need all that other crap in the box I opened it up to see if there was a separate module, sure enough there was.
 
The module is about 3X5”, powered by +14 VDC, had the GPS in and 10 MHZ/1PPS out along with 2 other pin-type connectors. Only 1 of the pin-type connectors was being used I’m guessing that is how it talks to the rest of the equipment. The other pin-type connector I’m guessing is for maintenance or trouble shooting.
 
After a close up look I notice the chip next to the unused pin-type connector is the same chip used by these ham kits to convert the TTL data from GPS engines to RS-232. I’m able to trace it out to the pins and find RS232 out/in. This is the message I got:
 
$GETVER 9.1.10 BOOT 10 6286 3bf5 06162200C1000A200627A1E0
 
It repeats over and over. I left it on for over a day and still the same thing. The 10 Mhz never stabilizes.
 
I’m powering it off of 14 volts and it starts off drawing about 1 amp, after a few minutes it drops to about a ¼ amp. That appears to be the OXCO warming up.
 
OK so here come the speculations and questions.
 
It’s been suggested that since the GPS is not mobile but in a fixed location, it has been told where it is or allowed to find itself then it will not search any more. I’m over a 100 miles away from where it came from It will never lock up?
 
Does the above string look like a message from the GPS or from other components on the board?
 
Almost forgot the GPS engine is a “Furuno GT-8031”
 
Any one have experience with this engine? 
 
Do you think I should be able to give it a command or do a hardware reset to lock up in it’s new location?
 
I would like to have this for the 10 Mhz out, NEMA data for syncing PC time and grid square would be a plus.
 
Sorry for the long email on first posting. Any help would be appreciated.
 
Chris
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