Peter, You can display signal strength vs az/el by pressing the letters "s a s" on your keyboard.
S = Survey A = Antenna S = Signals Sam. ----- Original Message ----- From: Peter Gottlieb [mailto:[email protected]] To: Discussion of precise time and frequency measurement [mailto:[email protected]] Sent: Fri, 04 May 2012 00:00:22 +1000 Subject: Re: [time-nuts] Something better than a Thunderbolt? > Interesting. I wonder what other GPSDO units are out there in the cell > systems > which might find their way to the surplus market? > > By the way, how do you get Lady Heather to show the plot of signal strength > vs > az/el? I tried all sorts of different graphing options and read through > everything I could find with no luck. > > Peter > > > > On 5/3/2012 8:02 AM, Mark Sims 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 -- [email protected] > > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > > ----- > > No virus found in this message. > > Checked by AVG - www.avg.com > > Version: 10.0.1424 / Virus Database: 2411/4975 - Release Date: 05/03/12 > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
