Re: VLF: First tests on VLF at DK7FC in Heidelberg

[Gary - G4WGT <g4wgt@tiscali.co.uk>]

Hi Stefan,

My 9kHz grabber is on 24/7 at the moment & regular captures at 30 minute intervals.

http://myweb.tiscali.co.uk/wgtaylor/9khz.html

73

Gary - G4WGT.

2011/6/9 Stefan Schäfer <schaefer@iup.uni-heidelberg.de>

VLF,

Tomorrow i plan to do first tests on 8970 Hz on my fixed antenna in Heidelberg,  http://no.nonsense.ee/qthmap/?qth=JN49IK00WG&from=jn49ik00WD It is about 30m up.

I'll start doing some resonating tests and may come on air in the afternoon. The small PA (max. 300W) will be used in this first test since it is easier to manage. Maybe the resonance will be some kHz higher but i hope to come down into the Dreamers Band (TM).

I expect to be visible on "local" grabbers like DF6NM, OE3GHB and OK2BVG. If all works well i plan to transmit a longer dash, maybe 6000 seconds and later a short message in DFCW-600, like "K" or so, just for the proof and to get a first impression about the efficiency of this antenna.

I had the idea to buy some flexible aluminium tube to form a toroid that will be placed on the top of the coil. Tis reduces the maximum E field and adds some C, that might be needed to come down to 8970 Hz...

Of course all this depends on the absence of rain but now i don't need wind! Therefore, the signals will be about 20 dB lower, probably.

The signal will be overload my grabber http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber.html that is in about 20 m (!) distance. Hopefully it gets not damaged due to several 10 kV on the wire.

Is there someone who will watch for that signal?

Reports would be very apprechiated!

73, CU, Stefan/DK7FC