Hmm. Based on your response, I bet I misunderstood the question. Been
working on finding element corrections for 432 this week.

tom
K0TAR

Mark Keith wrote:

"Xanax" wrote in message ...

Hi all,
I have a uhf yagi uda antenna mounted on the roof I have all the element
(alu welding rods) clamped to a alu- boom except the active elements.
Does this effect the preformance of the antenna in that the reflector and
directors are all connected from an electric point of view?

Cheers,
Xanax.


No. The driven element can be grounded to the boom also. Again, no
change, except you add a matching device. The connection is at the
high current/min voltage point. Being there is little voltage at the
center of the 1/2 wave elements, the boom is pretty much ignored by
the antenna. Also, it's at a 90 degree angle, which further reduces
coupling to the elements. My cushcraft tri-band beam uses an insulated
driven element, but most of the yagi's I build have all the elements
grounded to the boom. My three el 6m yagi has all the elements welded
to the boom, and the whole antenna, elements, boom, even the gamma
match tube, are all hard copper tubing. It's a one piece antenna. Or a
plumbers delight, as many call that method of construction... MK