Hi Jacek, Roger, VLF,
I have an idea:
Am 04.02.2011 19:00, schrieb Jacek Lipkowski:
you would achieve much larger distances if you tried qrss with a
better matched antenna. you can try this with overhead powerlines in
rural areas too if you can fit your signal between the harmonics. long
phone lines work well too.
What about a closed loop between two HV transmission line towers? These
towers are grounded by a cable on the top of the towers (lightning
strike protection). So there is no danger to operate here. One could try
to place a VLF or LF(!) TX between two of these towers, building a
closed loop. The loop current flows through the top wire of the towers
and the signal might be radiated over a longer section of the system,
like in a kind of gamma matched antenna.
Roger/G3XBM could try this e.g. here:
http://no.nonsense.ee/qthmap/?qth=JO02DG76TO&from=JO02DG76TB
I see no danger in these experiments since the systems are grounded.
Anyway there might be a current flow of some 10 A in that top wire.
Maybe it is possible to extract some current (perhaps some 10 mA) in
that loop and use a current transformer to build up the power supply for
the TX? :-)
Has someone tried that before? :-)
73, Stefan/DK7FC
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