Yes, Paul,
A half wave loop on 80m may not give as good a result, as it is an opened up
dipole folded back on itself. Certainly would cancel some of its radiation.
However, on all higher bands 40m and up where the loop is a wavelength and
more, it is a great antenna from our club experience. If a half wave high,
it likely is more of a DX antenna on 80m than ground wave antenna thus
explaining your result. Open wire line of any type can be used to feed the
loop at a corner with good result, and a tuner of course. You should not
need a 6:1 balun, but just a good quality 4:1 from our use of the loop with
several tuners. You can always add a few feet of balanced line to make up
for any mismatching problems. That shifts the impedance to one your tuner
can handle. We use an external Van Gorden 4:1 balun on the coax output of a
Tee tuner, and one foot of coax from tuner to balun. Then we have 300 ohm
or 450 ohm ladder line the rest of the way to the antenna.
Our loops exceed one wave around on lowest bands, and are only 20 feet high
for Field Day.
GL,
Stuart Rohre
K5KVH
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