Overnight run,

 http://abelian.org/vlf/tmp/170711a.gif

and here is the mean absolute phase difference
plotted over a range of time intervals,

 http://abelian.org/vlf/tmp/170711b.gif

This shows the average difference between two phase measurements
taken some interval apart.   Looks like beyond about 25 seconds,
it is about 0.14 degrees at 9765.625 Hz.    It is unlikely to
get any worse than this at longer intervals, being GPS locked.

For a LO at say 130 kHz, it would be about 2 degrees.   Good
enough for coherent reception at LF I think.

Amazing value for £17.00 and takes about 10 minutes to install
and set up.

--
Paul Nicholson
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