In a message dated 99-04-06 17:24:56 EDT, k1uo@banet.net writes:
> Does anyone have any first hand knowledge of which would "best" side
> mount directly to the 2 side legs of a Rohn 45 tower without the
> elements being overly close etc etc.
Are you going to rotate it or just leave it fixed? If it's fixed, just
about anything will work just fine.
A TH7 will turn around 45G on a 'swinging gate' sidemount and the
distance between the middle elements is 55 inches. The X-9 boom-to-mast
bracket is right up against one element and as I recall, the antenna is out
of balance to begin with so moving the bracket further back will only
exacerbate the situation. The X-9 distance is 44 inches. I think the distance
on the C-31XR is 30 inches.
But I don't remember what the minimum spacing is to get the antenna to
swing around 45G is.
>
> AND...which of these 2 antennas may be more succeptable to interference
> from a 2 ele CC shorty forty mounted at least 15 ft. away?
At that distance, just about any antenna will work just fine with
little or no interaction. When you get under ten feet spacing is when you'll
probably start seeing some interaction (manifested by increased SWR).
BTW, is it the 402CD or a new XM240? While the new antenna is basically
beefed up mechanically, my limited experience has been that it's also
different electrically. The one XM240 that I installed under a TH11 showed
MUCH MORE interaction than I've ever seen with a 402CD. Tom, N6BT, of Force
12 concurs with my observation. Even though it looks the same, there's
something different enough with the new design that it acts differently that
the older version electrically.
Cheers, Steve K7LXC
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