Herbert Schoenbohm <herbert.schoenbohm@gmail.com>
Thu, Aug 2, 10:04 AM (5 days ago)
to TopBand
I recently installed a 2 element 40-meter beam and a 4 element 20-meter
beam on top of a 90-foot tower which I use for TX on Topband. The tower is
cage fed with a 3-wire cage spaced24 inches around the tower, I am able to
get 1.2 to 1 on 1845 by putting about 1200 pf and a 500 pf fixed HV cap to
ground. The coax feed goes to the wires with about 40 mh in series. My
taps to the tower are at 60' which may be too high up on the tower
considering all the toploading I have now. My question is: How far down
should I move the tower taps to make the feed appear inductive rather than
the capacitive value currently what I believe I have?
Any suggestions would be appreciated.
Thanks,
Herb Schoenbohm, KV4FZ
On Thu, Aug 2, 2018 at 10:04 AM Herbert Schoenbohm <
herbert.schoenbohm@gmail.com> wrote:
> I recently installed a 2 element 40-meter beam and a 4 element 20-meter
> beam on top of a 90-foot tower which I use for TX on Topband. The tower is
> cage fed with a 3-wire cage spaced24 inches around the tower, I am able to
> get 1.2 to 1 on 1845 by putting about 1200 pf and a 500 pf fixed HV cap to
> ground. The coax feed goes to the wires with about 40 mh in series. My
> taps to the tower are at 60' which may be too high up on the tower
> considering all the toploading I have now. My question is: How far down
> should I move the tower taps to make the feed appear inductive rather than
> the capacitive value currently what I believe I have?
>
> Any suggestions would be appreciated.
>
> Thanks,
>
> Herb Schoenbohm, KV4FZ
>
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