[time-nuts] yet another GPSDO

Arthur Dent golgarfrincham at gmail.com
Wed Aug 12 23:44:33 EDT 2015


I made some progress with the Symmetricom CGBA card
I bought on Ebay and mentioned here last Friday. After
getting it running and checked out, I took a closer
look at the board to see if I could communicate with
it. What I found was 3 unused holes on the board marked
'USER' and 2 of those pads had runs going to an MB3232I
(MAX232) RS-232 chip. After I tried several things that
didn't work I finally got it to respond at 9600 8N1 and
typing '?' displayed the list of SCPI commands it accepts.
It was made by Samsung in December, 2003 and seems to
have an 8-channel receiver. I'll remove the onboard LEDs
and mount them on the front panel of the box I'm building
it into (I do like flashing LEDs!) and not have any other
display on the unit, the PC terminal emulator program
should be enough. There is a link below to a photo of 2
of the data screens it displays. I suspect the H/W fails
are because it isn't plugged into its intended backplane.

-Arthur

http://i906.photobucket.com/albums/ac262/rjb1998/CGBA%20screen_zpsbizmqype.jpg


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