On 9/29/2017 5:35 PM, Don W7WLL wrote:
I think I'll leave it in the sorta inv V form for the moment until I
decide what I want to do with 160.
In general, inv vee is a compromise configuration that most of us adopt
because 1) it's easier to rig or 2) we CAN'T rig it flat or 3) can get
the center a lot higher than we can rig both ends or 4) we want the
quasi-omni pattern that the inv vee provides (at the expense of strength
broadside). The simple fact is that the higher a horizontally polarized
antenna is the better it works.
Horizontally polarized antennas are just STARTING to work at a quarter
wave height, and a half wave is better. Few of us can rig a horizontally
polarized antenna for 160M at 1/8 wave (67 ft), and that's miserably
low. That's why verticals are almost universally used on 160M. Yes, they
DO need a counterpoise/radial system, and the better that system is, the
better the antenna works.
At one point I had a 160 dipole at about 120 ft in addition to a Tee
vertical that was about 80 ft tall with about 30 on-ground radials. I
did a LOT of A/B comparisons for the first year or two, and the vertical
nearly always won, often by a lot. The dipole was really weak in the 2-3
hours before dark -- running legal limit, I could reliably work 800+
miles, usually first call, with the vertical, but couldn't even get a
"QRZ?" with the dipole. Eventually the dipole broke and I never bothered
to replace it.
This slide show is mostly about 160M antennas and radial/counterpoise
systems, with a lot of attention given to small lots. None of it is
original -- I'm simply summarizing what I think are the best work by
others. http://k9yc.com/160MPacificon.pdf
73, Jim K9YC
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