Stefan, do you have measurements, dimensions, etc of your VLF
antenna?  I believe it is a wire strung between two buildings?

I was thinking of having a go at modeling it using LCnetgen

 http://abelian.org/lcnetgen/

to see if I can get the correct capacitance and if so, then
a good estimate of effective height might be possible.

I would need to know the approx dimensions of the buildings
to model them as grounded blocks, and the distance between
the wire ends and the buildings, ie the insulator lengths.

The reason for asking is that I've still not resolved why I
can't pick up your 2970Hz even with some 15dB of stacking gain.

> In a first test i measured 230 mA RF current and the
> power supply showed 0.94 A and 24.5 V. So that's just 23W
> including PA losses.

Should I look for a signal in my recording?

--
Paul Nicholson
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