FYI, back in the early 60's a company by the name of Gotham made
yagis out of galvanized electrical thin wall conduit type steel
tubing. The elements were relatively short and they used big
rug-beater looking wires at the ends for capacity loading to make
up for the lack of length. The popularity was good as they sold
for significantly less than their aluminum constructed
competitors. A trapped tri-band Gotham beam on a 12 ft. boom sold
for under $20 in that era. They also produced multii-band
verticals and the standard phrase at the time was "I've got a
Gotham vertical"! (or beam). They did eventually rust although I
know of one that was painted by its owner and was still in use in
the late 80's. -=Roger-K9RB=-
----- Original Message -----
From: Jerry Keller <dxdog@rcn.com>
To: <towertalk@contesting.com>
Sent: Friday, March 30, 2001 12:37 PM
Subject: [TowerTalk] Steel Towers vs. Aluminum Towers
> I would guess that the simple reason I've never heard of a steel
yagi is
> that although steel is strong, it's too heavy. Aluminum is
weaker in some
> ways, but also lighter. Considering the trade-offs, apparently
aluminum is
> usually the better choice for antennas. Apparently it's not the
same in
> comparing towers.
>
> Unless I'm imagining things, there seems to be a general feeling
on the
> reflector that there's a seriously significant risk of fatigue
failure in
> aluminum towers as opposed to steel. My questions are:
>
> (a) How serious is this risk? Have many actual failures have
occurred?
>
> (b) What are the practical variables that govern this risk?
>
> (c) Any practical steps that will minimize or lessen this risk,
and extend
> failure time?
>
> I wouldn't understand a scholarly dissertation (although if I
could, I know
> I could find one here!) but if anyone has some practical answers
to this, it
> would help me make my tower decision.
>
> TIA for your help, Jerry K3MGT
>
>
>
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