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Ham Radio

Eight days of data from GPSDO

[Today’s run: Limerock road – 4 miles]

I have now collected 8+ days of data using the FTS-4060 as my frequency standard, the Racal-1992 counter and my new little GPIB USB dongle.  I had one data point that was a wild outlier and I edited that.  (If someone wants the original data I could supply it.)

Here are pictures from the TimeLab program screens.

I am happy with these results.   Before I started this  I was able to recreate the standard deviation calculation which VE2ZAZ is using in his Windows program and add that to the logging that I am doing on my little linux box.  I wanted to see if that figure was a useful handle for saying how “good” the GPSDO is doing.  I think this data shows a correlation, at least enough for my needs.   I wanted something to tell me if my GPSDO was “ok” or whether it was faulty.  I see that the standard deviation calculation seems to fit the bill alright.  I wanted to be able to make a statement like:  When I ask this thing for 10 MHz, it gives me 10 MHz within a confidence window of +/- X Hertz.  The number I’m seeing is X=0.003.  Even that statement probably has errors because I don’t understand the statistics and what they really mean.

My data gathering is still going on.  But I am thinking I want to get back to using my radios and do some more ham-radio type stuff.  So I may disconnect this do a bit of reorganizing in the hamshack/evil-scientist/timelord  lab.

AllanDeviation

FrequencyDifference