Frank brings up the major fallacy in the lightweight aluminum
tower foldover paradigm. To really utilize the light weight of the
aluminum to advantage, you need to use a Hazer system like
on the Glen Martin aluminum towers. Of course it will have to
be a track mounted system and will have to be homebrewed.
Another way of getting around the dead weight problem is to
use the falling derrick method, if you have room for the
"derrick" to fall. It saves a lot of money on the gear motor
and acme screw, etc. Of course, the falling derrick method
also works with R25, etc, so why bother with aluminum at all
in that case?
Rick N6RK
donovanf@starpower.net wrote:
> Don't forget that you must comply with the dead weight capacity of your
> tilt-over tower. This is important, a nearby ham failed to comply with the
> dead weight specification and his Heights fold-over tower collapsed as he
> tilted it up. His mistake? He forgot to count the weight of his Heliax
> feedlines!
>
> Everything you add to your tower must be counted against the dead weight
> specification, including all cables, masts, rotators and other accessories.
> Give serious consideration to using an aluminum mast and light weight
> antennas, feedlines and control cables.
>
> Its especially important to minimize every pound of weight above the top of
> the tower (i.e., mast and antennas and feedlines). Every pound above the top
> of the tower adds very significantly to the moment on the lower tower
> sections and the tilting base.
>
> 73
> Frank
> W3LPL
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