RadioBanter - View Single Post

July 13th 03, 11:21 AM

(Richard Harrison) wrote:
Gary, K4FMK wrote:
"Do the same in the vertical plane also."

Never had a minor lobe identification problem.

Never improved over the bubble-level set of vertical elevation angle on
long paths either, but I always tried.

I had always calculated my path gains and losses, and my best received
carrier power was very nearly always within a db of my calculations. If
not, I had a problem. Fortunately, that was very rare.

Best regards, Richard Harrison, KB5WZI

Did you actually do very many?

The reason I ask is that there are other factors, and you
*can't* calculate them, and in some cases you can't even
adjust for them.

The best example that I know of was a TV microwave repeater that
was put in north of Tucson for a link between Tucson and Phoenix
back in the 1960's. This thing was located 50 miles from town,
at 8500 foot on a mountain top. They had a 50 foot tower
installed on a concrete base that cost $50,000 (think about that
in today's money!). And when all was said and done, they turned
it on, and it worked great!

But somebody had the smart idea to see what happens if they
slide the dish down the tower to see if the signal would
improve. It did!

So they positioned it vertically on the tower for best signal
strength. About 7 feet off the ground... :-)

(And darned if a few years later a build up of rhime ice on the
43 feet of tower above the dish didn't fall down and bend that
dish into a pile of ruble too.)

--
Floyd L. Davidson http://web.newsguy.com/floyd_davidson
Ukpeagvik (Barrow, Alaska)