Tim,
Unless you're using a *balanced* tuner, like the Johnson Matchbox or a balanced
L-network with the balun at the input (50 ohm) side of the network,
you cannot assume that your feedline is truly balanced. The impedance at the
end of your 32 foot run of window line is assuredly not purely resistive -
there is a considerable amount of reactance - and baluns don't handle reactive
loads very well.
An balanced feedline can easily become unbalanced if there are any metal
objects close to the line, even if you are using a balanced network for tuning.
I would not be surprised if your feedline is radiating - which may or may not
be a bad thing.
73 es GL!
Charlie N9CO
-----Original Message-----
From: Timothy Holmes <taholmes160@gmail.com>
To: Jeff Clarke <ku8e@bellsouth.net>; cq-contest <cq-contest@contesting.com>
Sent: Tue, Aug 23, 2016 8:56 am
Subject: Re: [CQ-Contest] How to start a run
Yes, the antenna is fed with window line. I dont remember the exact length
of feeder, but its close to 32 feet. Its got an LDG 4:1 balun and some
coax to make the shack entry
Tim
W8TAH
On Tue, Aug 23, 2016, 6:10 AM Jeff Clarke <ku8e@bellsouth.net> wrote:
> I believe the antenna that W8TAH described is NOT a dipole because he
> mentioned he feeds it with open wire feeder. A center fed zepp cut for 80
> meters is usually about 130-135 long and fed at the center with 450 ohm
> open wire line. The antenna patterns I described are on the W4RNL webpage
> and maybe the ARRL antenna book. I would imagine that if this antenna was
> fed with some type of 50 Ohm coax the pattern would be different.
>
> Jeff
>
>
>
>
>
> Sent from my Verizon Wireless 4G LTE Droid
> _______________________________________________
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>
--
Tim Holmes - W8TAH
Sent from my LG Stylo
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