In a message dated 99-08-23 18:09:18 EDT, firstname.lastname@example.org writes:
> >The weight of the C31Xr = lb 82 W/L 10.5 Sq.Ft
> >The weight of the XM240 = lb 55 W/L 5.5 Sq.Ft
> >The mast weight = lb 40
> >Total = lb 177
> I have a similar setup, a big KLM tribander just above the thrust
> bearing, and a 40-2CD Cushcraft short 40 just 6 feet above the
> tribander. The booms are in-line, not rotated 90 degrees, and
> everything works very well with no interaction that I can detect.
> I put the antenna with the biggest windload at the bottom of the
I think that a bunch of people (myself included) have run into
interaction problems with the XM240 where there weren't any with the older
402CD. You need lots of spacing - 10 feet or more. It was my experience
(XM240 & TH11) that turning the 40 ninety degrees made the problem worse.
The only difference in the two antennas that we could find to account
for the new problems was the fact that the reflector is insulated on the new
antenna where it was grouded with the older one. If anyone has a fix for this
problem (ground the reflector?), I'd love to hear about it.
I would give the HAM IV 2-3 years myself. That's too much antenna load
for that rotator. Since it's a used rotator, maybe even less.
Cheers, Steve K7LXC
Champion Radio Products
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