Thanks again Paul. The TX power had been raised by only 1 dB, and the antenna is the same. So the increased signal strength  seems to be mostly caused by different propagation during that time of the day.

Best 73,

Markus

Markus wrote:

> ...more carrier on 8270.0025 Hz from 15:25 until QRT at 17:00.

Measures 0.075 fT here which is distinctly stronger than your

usual signal, which recently has been around 0.05fT.

  http://abelian.org/vlf/tmp/160226b.gif

Shows up well on the spectrogram

  http://abelian.org/vlf/fbins.shtml#p=1456516800&b=120&s=sp

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Paul Nicholson

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