Could be a good day today for 9kHz tests, the background noise
is very low.

 http://abelian.org/vlf/nb.shtml

Now shows the amplitude spectrum when the loop pattern is rotated
to null the average bearing of the background noise.  This is the
blue trace, the red trace shows the omnidirectional pattern.

Noise floor 6dB lower.   Frankfurt signals will be 3dB lower
with the prevailing noise bearing of 70/250.  Usually the daytime
noise is more like 30/210 and with this nulled, Frankfurt will be
almost 'on the beam'.

Getting closer...
--
Paul Nicholson
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