Gerhard
Nice looking coil. What are you using for a form?
Jay W1VD WD2XNS WE2XGR/2
----- Original Message -----
From: "Gerhard Hickl" <[email protected]>
To: <[email protected]>
Sent: Sunday, March 20, 2011 3:14 PM
Subject: Re: LF: VLF
Hello Mal, group!
As far as I know, Markus and Ossi both use multi layer coils. They are
very compact but with the known problems regarding insulation. I think
Markus meanwhile has also a single-layer "stack"-type...some flower pots
building a stack.
My coil is a single layer type with variometer inside. Basically the
same design that Stefan has in use, just a bit bigger.
It is calculated for about 100m vertical wire (=roughly 600pf, pretty
much the same as my fixed antenna has) and the inductance is about 450
to 575mH. DC-resistance is about 140R.
I will have to make some taps for longer wires (kite) but I had no
chance to give it a try.
See the two pictures enclosed.
I was transmitting from about 00:00z today until now on 8969.98 with a
break of about 90 minutes in the early afternoon. I switched to full
power roughly at 10z. The power I used before was about 6db lower in
order to maintain safety while the equipment was unattended. This
produced a nice trace on Paul's receiver.
73
OE3GHB
Gerhard
Am Sonntag, den 20.03.2011, 16:17 +0000 schrieb mal hamilton:
It looks like all VLF acty has ceased today. No indication about what
is going on.
Those using large coils to resonate kites and balloons, are these
coils single layer or pile wound, multi layer etc
A lot of turns would be needed for single layer and insulation
breakdown could be a problem for pile/lump wound.
de mal/g3kev
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