On 4 Apr 2007 16:38:23 -0700, "art" wrote:

All very fascinating at least for non amateurs.

We've been doing it for years on repeaters. It's called "down tilt"

eBay has kits for sale as does:
www.hotflashesatthetower.com (Andrew Antenna Down Tilt Mounting Kit
602030A. US $9.99)

Proving anything can be patented, that was done 10 years ago:
5798675 Continuously variable phase-shifter for electrically
down-tilting an antenna

and on and on and on....

73's
Richard Clark, KB7QHC