Am 26.09.2013 02:50, schrieb Bob Raide:
Stefan;
If you get time can you show me where the sphericas electrode would be
placed? Maybe at the ant end?
Add it where you can see it sparking. You can use more simple
arrangements to prevent arcing though.
But preferably i recomment to increase the top load capacity of the
antenna. This will reduce the voltage and the coil losses. The coil
losses could be in the range of 30 to 60 % of your total losses i guess.
I have figured you have 10 db on me on 137! You are
in here almost every night regardless of conditions!
That is nice. I hope i can hold this situation as long as possible. But
they are building another building in 30m distance of the antenna. This
will not improve the situation :-( Sometime everything comes to an end,
we know.
I see pictures of your 9 kHz gear and the land is flat
and I would bet your soil conductivity is very good.
The 8.97 kHz experiments were done at a different location. This
location was excellent, until they installed a 2 MW wind generator
there. All experiments were /p, so i had no permanent earth system
installed there. I used a long copper plate and a few earth rods on
VLF. I a short experiment i transmitted in CW and so i had to add a C
of 60000 uF (350V) to the PA, so the generator just sees an average
power. There i got 1.7A antenna current on 8.97 kHz in a 300m vertical
antenna. The signal was audible in 40 km distance which is more than 1
Lambda. More could have been possible but there were no listeners in
that sort of distance. But in DFCW-600 i managed to be visible in 4X,
TF, EI, G, F, ON, PA, SP, OE, I, OK and YO. Nice to think back to these
times :-)
73, Stefan/DK7FC
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