The answer is probably in the data you didn't give us. If this was an L
made from something like #12 wire held up by a tree, it would be a very
good match for 50 ohm coax, so about 1.5 SWR for 75 ohm line.
So what is the support? A tree? Or maybe an insulated tower being fed
as the vertical portion of the antenna, or is the tower just holding up
a wire inverted L next to the tower? If that is the case, what is on
the tower? Yagis? Other wire antennas? Insulated or non-insulated guys?
All this will contribute to loading on the tower. In this is the case
the resonant point of the tower is the important parameter. If it is
near 160 meters it can cause all kinds of problems.
Jerry, K4SAV
DENNIS BRICKEY wrote:
>I realize this is not a tower question, but the antenna gurus hang out here.
>Hopefully some bandwidth can be tollerated for an antenna question.
>
>I am working on a 160 meter inverted L and having some difficulty getting the
>match correct. I'd appreciate any input.
>
>175' total wire length.....100' vertical 75' sloping horizontal
>
>23 (qty) 130' radials.
>
>Fed with 75 ohm cable hardline through a variable capacitor.
>
>I've trimmed and extended the vertical section and adjusted the cap with each
>length change. The low swr point is always 2.8:1. Essentially the only thing
>changing is how
>
>much the capacitor meshes.
>
>I started with 16 radials and thought adding more would help the match, but it
>has not changed.
>
>Any Ideas?
>
>All advice appreciated.
>
>Thanks,
>
>Dennis N4DD
>_______________________________________________
>
>
>
>
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