Hi Roelof,
Hmmm, i would say it is the frequency response of the front end of the
antenna. The input frequency spectrum is that of a discharge of a
charged rain drop through the RC network on the input. Maybe protection
diodes could help here, a bit. They could become conductive and lead
the biggest part of the charge towards GND.
On the other side your probe is protected against direct water contact,
so no galvanic connection. Anyway there is an electric field building
up arround the probe when a charged drop is falling on the wet tube
arround the antenna and there is a dynamic current flow against ground,
so it will have a frequency spectrum that you seem to observe...
73, Stefan
Am 18.04.2017 11:52, schrieb Roelof Bakker:
Hello all,
Last night reception on 630m was severely effected by static rain.
See attachment.
I have often noted that the effect of static rain is worse for > 450
kHz and that it is almost completely gone below 300 kHz.
Does anyone have an explanation for this phenomenon?
73,
Roelof, pa0rdt
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File: Static Rain.jpg
Date: 18 Apr 2017, 11:45
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