John, you could consider the two balun wires to be a balanced transmission
line and model the effect of that. For example, if the wire spacing was 4
inches and the diameter was .1in the impedance would be about 525 ohms. If
the length was 6 inches, at 14 Mhz it would be 2.6 degrees long.
Connecting a 50R termination to that and using transmission line software
would result in a 50.1 +j24 value. The antenna feed point would need to
present a 50.1 -j24 value to match.
Gerald K5GW
In a message dated 5/27/2016 8:10:24 P.M. Central Daylight Time,
john@kk9a.com writes:
Yes the balun leads are part of the antenna. I have not ever modeled them
and I typically have to shorten the DE a little. Is there an easy way to
model these, it is such a short segment and the leads are somewhat
parallel.
John KK9A
To: <towertalk@contesting.com>
Subject: [TowerTalk] Change in Frequency with Height above Ground
From: "Jim Thomson" <jim.thom@telus.net>
Date: Fri, 27 May 2016 14:25:26 -0700
The wire leads from balun to feedpoint will also lower the resonance
point.... but that is moot, since most folks know the leads are a part of
the ant.
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