Tom W8JI wrote:
>What I used, when I had limited space, was a simple 100 foot long
>dipole with balanced feeders down to the ground. I could feed the
>antenna as a T on 160 and 80, or as a dipole on 80 on up. I had to
>switch networks outside. Of course it needed a ground system, as
>all verticals or antennas near earth do if you want high efficiency.
I used something similar - a half-wave dipole on 160m with a paralleled
half-wave 80m dipole, fed with 450 ohm plastic ladder line. In the shack, a
choke "balun" and an unbalanced ATU, with a bunch of random radials all over
the garden. Worked great on all bands. 80m half-wave was added because I
could not easily match the full-wave alone on 80m. No idea what the radiation
patterns were like: antenna was only about 60ft up in the trees so probably
radiated all over the shop on LF. No real sign of any 'end-fire' on higher
bands either - too many lobes I guess.
BTW, in HF Field Day, I always lay a big set of radials ... & we usually win.
73,
Gary ON/G4iFB
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