Some plots of NAA amplitude and phase for the recent few
days

 http://abelian.org/vlf/tmp/naa140301.png
 http://abelian.org/vlf/tmp/naa140302.png
 http://abelian.org/vlf/tmp/naa140303.png
 http://abelian.org/vlf/tmp/naa140304.png
 http://abelian.org/vlf/tmp/naa140305.png
 http://abelian.org/vlf/tmp/naa140306.png

140301 was upset by geomagnetic activity and you can see a
solar flare at about 13:15.  Some smaller flares occur on
subsequent days.  NAA off for a few hours on the 3rd.
5th and 6th seem more typical after the ionosphere has
got back to normal.

Interesting that there's a little amplitude peak just
before the sun hits the path.  LWPC predicts a similar
peak at 29.5kHz.

Increasing ionisation due flares is increasing the signal,
as does the solar peak at the center of the path which
we would expect to be at 14:00 or a little later.
--
Paul Nicholson
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