I have been using Full wave loops on 80m since 1987 and have always used 75 Ohm
coaxial cable as feedline without a Balun. I know of other hams that use a
Balun on a full wave loop. My Loop is Rectangular in Shape and fed in the
center of one of the shorter sides. The Antenna is terminated with a gap of
around 3 inches between the ends.
This was how it was described , for a German Quad antenna which is a Full wave
loop in a Diamond shape terminated at one of the sharp pointed ends..The German
Quad was Quoted with an Impedance of roughly halfway between 50 & 70 Ohms
Impedance.. My Quad antenna is 33 feet high at all 4 points. Any Comments on
what impedance this Antenna May be at the feed point and how to feed it with
Coaxial cable... I am about to run ALL new cables thru the roof of My House and
I'm wondering whether to use 50 or 75 Ohm Cable...
73
Lee Noonan VK2LEE
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