On 7/24/2024 4:13 PM, kq2m@kq2m.com wrote:
I mentioned "one antenna that does work well even over poor ground", not
the best antenna overall. And it does work very well - enough to let me
work 39 zones and 300+ countries on 80 not to mention being a very
effective antenna in DX contests when the K index is below 5.
I looked at the FCC map, and you're right, Bob, your soil conductivity
is poor. Thus, the principle advantage of your array as compared to a
high horizontal dipole is directivity, NOT gain. And yes, elevated
radials could be a good design choice. But there's a lot more to radial
systems than most hams are aware of -- Rudy Severns' work, published
about ten years ago in QEX, is required reading for optimizing their
efficiency (and thus both field strength and directivity).
On the basis of the serious modeling study I did ten years ago on how
horizontal and vertical antennas are affected by height and ground
quality, I'd take a wild guess and say that its Gain is probably fairly
close to my dipoles at right angles to each other at about 120 ft, and
that its directivity in the horizontal plane is significantly better. I
have to get RX directivity from dedicated RX antennas. And your
contesting station is competitive because you're on the east coast; it
wouldn't even be in the game if it were in W6. :)
The effects of ground are to attenuate the signal in the near field, the
far field, and to form the vertical pattern. Those losses ONLY affect
transmission, not receiving.
As to 80M DX -- I've been in W6 for just under 18 years; I'm missing
zones 22, 34, and 40. I have 239 countries on 80. Note that low band
countries count is FAR easier from the east coast than from W6. Yes,
Asia and OC are tough from the east coast, but there are FAR more
countries easily workable from the east coast than from W6. :) So DXCC
achievements are NOT a measure of antenna effectiveness.
Choices of antennas for most of us is strongly dependent on our real
estate, our finances, and what we want to work. Your choice was a good
one for you. That 80M choice isn't even possible for me.
73, Jim K9YC
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