I would run high Z open wire feeder to it, it will then even work on
75m with very little degraded performance compared to a 1/2wl for 75m,
less then a dB.
Best is to get a good balanced tuner, something like an old faithful
Johnson Viking matchhbox.
It is very very easy to make a 400-600 ohm feedline yourself and the
material wouldn´t cost many dollars at all, if you dont run super
high power it can be made very light weight.
To answer your questions, no dont shorten it, dont worry about the ends
in the foliage, best performance increase is to go to open wire feeder,
if it sags down a few feet no big deal.
73 Jim SM2EKM
----------------
Art Boyars wrote:
> On the CQ-Contest Reflector K7QQ said: "You have to keep in mind that the
> best antenna doesn't exist. You can only get up what you can and it is never
> enough." Well that's where I am, but I'd like advice from you experts on how
> to improve my antenna, within my personal constraints.
>
> My antenna is a dipole, about 99-ft long, strung between maple trees of the
> neighbors on either side. (It's already much higher than the peak of my
> roof. No other supports available.) The feed line is mostly window-pane
> twin lead, with several feet of coax to get into the house and reach the
> Transmatch. Yeah, I know it's not balanced; but should I really care, as
> long as the RF goes somewhere other than losses? (And I know that the high
> SWR might cause the coax to arc over or have noticeable resistive loss, but
> that's one of the constraints -- for now.) My main operating interest is SS
> CW, with a little other casual contesting (work the Club members and the big
> guns) and a bit of 40M CW DXing (if I can get the antenna to work better).
>
> I've pulled the ends of the dipole as far as I can into the trees (maybe too
> far), but it still sags quite a bit -- 5 to 10 feet, by eye. Some of the sag
> is probably from the weight of the antenna wire and the feedline, but I think
> a lot of it is simply from the dipole's being longer than the span between
> the trees.
>
> I have two seat-of-the-pants concerns. First, I may be getting losses from
> having the ends of the dipole in the foliage. Second, the vertical-V might
> be more NVIS-like than Iis good for me. Obvious solution is to shorten the
> dipole a bit, but that would make it even shorter than the recommended 100-ft
> minimum. So, first question for the experts: Do you think I'll do better to
> shorten it, or should I leave the ends in the trees?
>
> Second-order solution and question: If it turns out that the feed line is
> weighing down the center, would I be better off to let it sag than to change
> to something more like TV twin-lead? (I recall some discussion here about
> Radio Shack selling a twin-lead with heavier-than-typical conductors.)
>
>
> Thanks for your help.
>
> 73, Art K3KU
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