On Sat, 27 Oct 2007 19:44:30 -0400, Tam/WB2TT wrote:
"Barrett" wrote:
I have two beams I want to install on the same mast. They are, Cushcraft
MA5B and an 9 element crossed Tonna.

What is the optimal distance that these antennas should be spaced?

What is the minimum distance apart can they be mounted before they have a
negative effect on each other?

Does it matter what beam is mounted on the top?

Does it make any difference how close the beams are mounted to the
rotator?

This is the first time that I have put any beams up, so I thought I better
get some good advice first.

I have a tubular tower, with no way to have a thrust bearing. So, I have the
Hygain TH3 tribander resting right on top of the rotor flange. 6 m beam is 7
feet up from there, and 2 m beam is half way in between. I care more about
6 than I do about 2 meters. I did run an EZNEC simulation of my 6 m beam
with/without an HF beam 7 feet below it; there was no change in performance.

Almost an identical lash-up here, Tam. The CC A3S is at the bottom of
the mast, the CC 215WB is halfway up the mast, and the CC A50S is at the
top. The mast is about 6-7 feet high:

http://jonz.net/W3DHJ/images/W3DHJ_Tower.jpeg

The OP needs to ask whether or not the antennas radiate best when dis-
assembled in the gargae, or up in the air and connected to coax? HI!HI!

73
Jonesy
--
Marvin L Jones | jonz | W3DHJ | linux
38.24N 104.55W | @ config.com | Jonesy | OS/2
*** Killfiling google posts: http://jonz.net/ng.htm