Re: New station on VLF: DK1IS

[Paul Nicholson <vlf0403@abelian.org>]

Thank you Tom, that was a most interesting post with much food
for thought.

Nice construction and good to see an alternative to air-cored
loading coils.  The increase of inductance with current is
curious.  An artifact of the test setup?  Interesting point
about the audio channels being out of phase.

Do you have any feedback from an E-field probe to stabilise
the phase?  Perhaps that's not necessary with the relatively
low Q system.

The antenna wires spaced one 1 metre - I assume 1 metre between
each wire.  The 160 ohms antenna resistance, that must be
mostly ground resistance?

> It´s always a little bit frustrating that I can´t hear my own
> signal even at the VLF RX site at our club station DL0AO only
> 6 km away in a forest.

Sometimes they become audible when a long transmission is
played back time compressed.   I tried that with your 28th
carrier but even with x20000 compression it was still not
audible.

The ferrite chokes look a lot like RS components 715-6857,
which happen to be the same ones I use for filtering in
my 48V rx power supply.  10mH, Rdc = 3.394 Ohms.

--
Paul Nicholson
--