[TowerTalk] Breakall short vertical

Tom Rauch w8ji at contesting.com
Fri Jun 11 08:18:49 EDT 2004


> Am I right to assume that although the feedpoint impedance
is 50 ohms, the
> ground loss picture is really closer to that of a single
short inverted L,
> and is established by the feedpoint impedance of a single
L rather than the
> 4 together?  Any other comments on the antenna?

You are correct Pete. The ground losses are identical to a
single antenna. What you essentially have with multiple
drops is an impedance matching system. The multiple top
wires might spread the E- and H- field losses of the
horizontal wire around, and could reduce them a little bit.
I'd have to think about that a while, hi hi. Otherwise, it
is the same as a regular Inverted L the same height. You
have the same ground currents, and the same ground losses.

Multiple drops and folded elements do NOT reduce ground
losses, since the sum of currents flowing into the ground
always remains the same independent of how many drops the
antenna has for a given antenna height.

There is no such thing as a free lunch. You would need a
good ground.

73 Tom




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