In a message dated 99-12-26 15:38:36 EST, K7NV@contesting.com writes:
> The only reasons for using a configuration with a cantilevered top tower
> section would be to gain more antenna separation than available on the
> mast alone and/or have independently rotating antennas near the top.
> This approach certainly doesn't come without its cost of reduced antenna
> loading.
The reason is that the typical Rohn tower configurations are for
'commercial' installations - not typical ham ones. In the general notes it
mentions the symmetrical mount of 8 sq.ft. This is for commercial standoff
mounts and omnidirectional antennas. The exposed tower above the top set of
guys gives additional clearance for these verticals.
I've never seen a ham configuration that was 'helped' by cantilevering
the top section. OTOH I've seen at least one tower where the rotator was
above the top set of guys and the wind eventually broke some tower welds
(this was not a Rohn tower).
Cheers, Steve K7LXC
Tower Tech
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