"JIMMIE" wrote in message
oups.com...
While operating on 10M I have observed that a halfwave vertical dipole
will communicate to different areas than a 1.25wl vertical monopole an
example would be that during a band opening the 1/2 wl antenna may be
working predominantly into New York while the 1.25 wl antenna is
working best in California or was it vice versa. This has proven
useful for me, instead of fighting a pile-up and can just talk
somewhere else. The two verticals may soon be replaced with a tri-
bander and I was wondering if I could get this same type of effect by
tilting the antenna vertically(no change in polarity) with a remote
controlled device. I think it would be pretty cool to hear different
areas of the country pop in and out as the elevation of the antenna is
changed.

It would work, theoretically, for a small change but I doubt you'd ever
notice the effect.

You need a very directional (many elements) antenna to see a big difference
in the amount of signal in the elevation plane. High gain UHF TV antennas
do have tilters, but it's to match the angle of arrival of the signal, which
may be coming out of a duct or reflected off a nearby ridge. See a sample
at http://www.atechfabrication.com/prod...omy_tilter.htm

Most tribanders are three elements and have a 3dB beamwidth of about 60
degreees in the azimuth (plan view) plane -- worse in the elevation plane.

Further complication: The ground affects the shape of the elevation
pattern, maybe more than any tilt you could apply. You might better
fine-tune the angle of arrival by cranking a tower section up and down.

"Sal"