Topband: Shunt feed vs sloper

[R. Dean Straw]

Bill:

Concerning quarter-wave slopers:

<snip>

> I believe the current thinking is that they act like an inverted Ground
Plane
> so they MUST have some sort of top-loading (usually one or more Yagi's)
for
> them to work properly.

Modeling shows that this is true -- the Yagi acts like a top "counterpoise"
for the sloping wire. Indeed, removing the tower from the model essentially
doesn't change the feed-point impedance nor the radiation pattern for the
sloper.

Anyone who wants a copy of the EZNEC modeling files can ask me directly by
e-mail.

73, Dean, N6BV

n6bv@arrl.org