I don't think your TTi TF930 has a GPS input to calibrate against, based on a quick perusal of the data sheet. I would guess that the calibration constants are thus fixed from the factory (including temperature coefficients).
On Thu, Feb 26, 2015 at 3:36 PM, James via time-nuts <[email protected]> wrote: > I presume that this is what my TTi TF930 does. Calibration is closed box > so I guess the TCXO is free running and the micro inside just uses > calibration constants. > > James > > > > > > > > > -----Original Message----- > From: Paul Alfille <[email protected]> > To: Discussion of precise time and frequency measurement < > [email protected]> > Sent: Thu, 26 Feb 2015 19:02 > Subject: [time-nuts] Measuring frequency rather than tuning crystal > > > I have a couple of HP 5370s with the beaglebone brain transplant. They > come > with a nice 10811 that has a little adjustment screw. > > Testing against a > Thunderbolt or KS-24361 the 5370 is off by less than 1Hz. > > I know the > traditional method would be to adjust the crystal slowly and > make careful > measurements, but since I have a fancy computer in there, I > wonder if I could > just adjust the frequency in software. 64-bit floating > point numbers should > have sufficient accuracy. All reported measurments > would be corrected for the > actual reference frequency. > > Basically, I'd have a 10000000.226 Hz internal > reference. > > In fact, could I connect the beaglebone to a a GPS 1 pps source > and make > this a GPS-disciplined-software-corrected oscillator. > > So my > question is is this a known technique? The discipline feedback > circuit seems a > little different, I'd adjusting for drift and offset, but > not the gain of > control-oscillator > linkage. > _______________________________________________ > 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. > _______________________________________________ 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.
