In a message dated 9/3/01 5:42:37 AM Pacific Daylight Time,
alsopb@gloryroad.net writes:<<
CQ's July issue had an article on a horizontal loop.
It was entitled" Remote tuned Loop for HF DX"
The article pulled no punches on the difficulties of matching this
antenna on different bands. The article addressed a "160M square
loop" and had the following table of impedances:
1.8 MHz 75-10j impedance
3.8 189+213j
7.15 331-413j
10.1 2395-330j
14.2 550-696j
21.3 1079-691j
28.5 1163-194j
I would imagine that these impedances would roughly scale for loops
designed at lower primary frequencies.
Most of the article was devoted to the design of the remote tuner
required to match this antenna.
Bottom line: If you intend to use this type of antenna effectively,
you better figure out how to remotely tune it.
73 de Brian/K3KO
>>
Why not use multiples of 135' of .98 VF open wire line and do the matching
inside the shack where it's far easier to do? I've used it and variations
for many years. I suggested on TT the "K7GCO Magnum 2X Version" for Field
Day that is twice as long strung up between football field light poles. This
loop gives max gain possible on all directions with progressive gain at the
higher frequencies for a simple antenna and it's size. The Magnum 2X Model
(294' on a side) will be end fire 160-6M. k7gco
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