Dear Mike Bill, LF Group,
At 23:38 06/10/2002 -0500, you wrote:
Most definitely. Scale a 15-meter by 15-meter square vertical loop up for
the 136kc band, and look out. It will work great and you won't start any
fires either.
15m * 185kHz/136kHz =20.4m
If we all had 20.4m high antennas, we wouldn't be using kilowatts either!
I remain to be convinced about the benefits of loop TX antennas - a lot of
any advantage to US Lowfers seems to be due to interpretation of the "part
15" regulations with regard to antennas - if you have the choice of a tuned
wire 15m long in total , or a 15m by 15m loop, it is not surprising that
the latter is a better bet - it is a much bigger antenna, after all. This
choice does not apply on 136k. From a practical point of view, where most
peoples' best available antenna is restricted by the number and height of
supports that can be used, and the planning permission difficulties they
cause, it is much more difficult to keep all that litz wire in the air,
rather than have a skinny wire aerial, and keep the litz wrapped round the
dustbin!
Cheers, Jim Moritz
73 de M0BMU
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