I would recommend also matching the open wire line (or ladderline) to
the antenna at the antenna end. If you did all the matching at the
shack end and had 2000 ft of Wireman 551, the feedline loss on 80 meters
would be about 6.4 dB. On 20 meters it would be about 9.6 dB. You also
need to take care of the balanced feedline to unbalanced antenna
problem, otherwise the feedline will radiate a lot, and with that length
of feedline, could become the primary radiator instead of the vertical.
Even with a matched load and using 2000 ft of Wireman 551, the feedline
loss should be about 4 dB at 10 MHz. I would look closely at building
some custom open wire line which can be made to have lower loss, and use
a matching system at both ends.
Jerry, K4SAV
Joe Giacobello wrote:
> If one had to install a ground mounted vertical as far as 2,000 feet
> from the shack and wanted to avoid the expense of using low loss coax,
> could a balanced feedline be used as an alternative? The idea would be
> to run the balanced feed line to the base of the antenna and connect to
> the antenna through a current balun. The input to the feedline and the
> antenna would be matched by means of a balanced tuner in the shack.
>
> Anyone have any thoughts on the effectiveness of this arrangement?
>
> Thanks and 73,
>
> Joe
> K2XX
> _______________________________________________
>
>
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