Topband: Shunt feeding a tower with side mounted yagi

[Herb Schoenbohm]

Geroge,

Depending on the beams size, location on the tower above ground, and the
frequency you are using, it could decouple the top portion. Instead of linear
loading, a beam at mid point, in my view, would give you some linear
decoupling, and this would be detrimental to the overall efficiency of the
antenna.  Assuming the shunt feed is higher then the side mounted it could
shorten the electrical height to the tower especially if the yagi is large and
fairly close to the ground.  If the beam is closer to the physical top of the
tower and the other antennas are on a mast above this one, you should not worry
to much since the top loading will still be achieved.  I suppose someone with
ELNEC will be able to model this and declare I am all wet.  I can only go by
the old fashion AM broadcast knowledge that top loading really needs to be at
the top. If you find out anything on this please let me know.

Herb Schoenbohm (ex-KV4FZ)