Once you get the frequencies matched with a fraction of 1 Hz, I would measure the phase between the 10 MHz source and the 10 MHz from the Trimble.
On 12/14/2011 12:29 PM, George Dubovsky wrote:
List; OK, I need to measure the stability of a 10 MHz sine-wave source. After reading a lot of background info on this list and some of the sources that were referenced, I thought I could get away with a frequency measurement. I now think I was wrong. What I have is an Agilent 53230A counter (a pretty capable box - claims 20 ps one-shot resolution in TI mode), a Trimble Thunderbolt, the 10 MHz oscillator to be measured, and a copy of Stable32. My first effort involved feeding the Trimble 10 MHz into the counter as its Ext Reference. I then fed the Trimble 1pps into the Ext Trigger input of the counter and fed the sinewave 10 MHz signal to be measured into Ch 1 of the counter. I then captured the frequency reading of the counter every second and stuffed those numbers into a file. I collected about 20 hours of frequency readings, but when I imported that into Stable32 and attempted to do an Allan Dev plot, it didn't look very good - specifically, the sigma numbers were in the region of 10e-2 to 10e-4. So, I grabbed another Thunderbolt and attempted to do the same measurement on it, figuring that everyone (but me) has taken data on a T'bolt, so I could just look on tvb's site or some such to find proper data on a Tbolt. Again, the plot didn't look like it should. Am I going to have to go to time interval measurements to do what I want? And does this mean I will have to square up my 10 MHz signal to have real edges? geo _______________________________________________ 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.
-- Chuck Forsberg WA7KGX N2469R [email protected] www.omen.com Developer of Industrial ZMODEM(Tm) for Embedded Applications Omen Technology Inc "The High Reliability Software" 10255 NW Old Cornelius Pass Portland OR 97231 503-614-0430 _______________________________________________ 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.
