My apologies if is missed it, but will there be "official" support of the nortel version in some future release of LH?
On Thu, May 3, 2012 at 5:02 AM, Mark Sims <hol...@hotmail.com> wrote: > > Recently Sam managed to poke and prod a Trimble/Nortel GPSTM (NTGS50AA) > enough to wake it up out of its slumber and be recognized by Lady Heather. > The NTGS50AA is a version of the Thunderbolt done for Nortel. It has some > interesting features (like hot-upgradable firmware, single 24 or 48V power > input, cheaper than a tbolt, etc. It also has a few warts... no TSIP > command documentation being the main one and a few commands are definitely > different than the Tbolt. > The wakeup technique is rather crude and can take a couple of minutes (shout > a particular command into its ear until it wakes up). Trimble's software > manages to get it talking immediately. Duplicating the commands that Trimble > sends does not seem to work. Once it wakes up, it stays awake until you > power cycle it or run Trimble's software. > > I purchased one of these units from an Ebay seller in Old Cathay (around $70 > or make offer plus $30 shipping) to see what it would take to add support to > Lady Heather. My unit came in a week or so later. I hacked a 48V power > connection (literally) onto the board and powered it up with a wall wart. > After some futzing and puzzling over the proper ribbon cable orientation > between the main board and front panel board, I got the unit woken up using > Sam's technique and puzzled out the commands to make the oscillator > disciplining (time constant, damping, dac gain, etc) work. The old survey > location was in a sketchy Guatemalan smuggler's haven border town at what > looks like a private residence. > > After running it a while, it became apparent that it works better than the > Thunderbolt. The temperature sensor does not have those glitches that plague > the tbolt. The receiver has a bit more sensitivity. And, best of all, the > oscillator is pretty much immune to external temperature changes (the Tbolt > oscillator makes a good thermometer). The reported OSC and PPS rms errors > are exceedingly low... you have to actively thermally stabilize the Tbolt to > approach these numbers. Hopefully this quality extends to its phase noise, > etc spec. It would be interesting to see what thermally stabilizing the unit > would do... > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. -- --Eric _________________________________________ Eric Garner _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
