Thanks Thomas, for the link to the TM-4M. It appears the TM-4M is a much
newer and fancier unit than these things. There may be some operational
and HW similarities, but the ones I have are about twenty years old, and
are clearly bigger (large single-board) than the dimensions of the newer
type
I have it temporarily rigged now with both units apparently operational
and locked. I changed the antenna pigtail leads on the GPS RX units from
TNC to SMA for more convenient HW experiments. I disconnected the DC
feed from one and loaded it with a dummy resistor, so only one provides
antenna p
That looks like a re-packaged Spectrum TM-4M: https://i.imgur.com/VKZtQzr.jpg
With the internal lead battery and routing to different front
connectors removed, it looks quite alike.
If so, they can do either their custum binary protocoll or NMEA. I
have been meaning to suggest for Mark Sims that i
I recently picked up some old cell base station units, and retrieved two
of what appear to be this unit, from Spectrum Instruments:
http://www.spectruminstruments.net/products/custom2/custom2.html
I have asked them if any info is available, but no response yet. If
anyone knows anything about t
