[time-nuts] Samsung GPSDO : Chinese surplus

gandalfg8 at aol.com gandalfg8 at aol.com
Thu Sep 20 16:55:09 EDT 2018

I had to make several changes to Lady Heather to work with these...  you may have an earlier version.

How are you connecting the serial port?   In the photo, I did not see the row of four holes that is on the Trimble / Symmetricom versions.

Hi Mark

The serial port connections are on the 50 pin flatstrip header, as per diagram here......


That's based on the Trible/Symmetricom versions and is shown with the connector removed but so far what I've checked matches up.
Fortunately my unit was supplied with a breakout board to convert the flatstrip to a double row of 0.1" spaced holes, and a couple of rows of header strip plus an old flat SCSI cable fitted a treat:-)

I realised there must be variations with this one over and above what you'd sorted earlier but thought it worth a mention in case it gave you any pointers, the real issue though is still that as it stands it can never boot into GPS mode without outside intervention anyway.
I did wonder if it could have received the appropriate configuration commands for whatever unit it was sat in but that should have been obvious to anyone who powered one up, which it might have been of course:-)

For now I've switched to the view that this one may have either a hardware or software fault that's preventing it booting up properly and am currently awaiting further response from the seller.

As it stands it's certainly not a very practical option if it needs a permanently attached PC to manage the boot up, although once booted it is looking quite good, as is the little Ublox LEA-6T.

I'm still intrigued though by the very existence of that EXT/GPS software switch as a configuration option for the GPSDO itself, and wondering just what EXT might actually imply in this instance. 

Nigel GM8PZR

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