[TowerTalk] Taller tower, shorter mast or vice versa?

[David Robbins K1TTT]

20' of mast out the top of a tower is not only a big strain on the mast,
but also on the top of the tower.  Be sure that the tower, bearing, and
rotor combination can handle what you want to put up there.  It is also
much harder to service if you don't have a bucket truck handy... in fact
any more than as high as you can reach standing on top requires much
more work for installation and maintenance.  I would consider things
like ring rotors and side mounted fixed antennas before trying to push
up 20' of mast with antennas above the top of any tower.


David Robbins K1TTT
e-mail: mailto:k1ttt at arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
 

> -----Original Message-----
> From: towertalk-bounces at contesting.com [mailto:towertalk-
> bounces at contesting.com] On Behalf Of Alan AB2OS
> Sent: Wednesday, July 21, 2004 22:46
> To: towertalk reflector
> Subject: [TowerTalk] Taller tower, shorter mast or vice versa?
> 
> The township rules permit an antenna/tower/mast up to a max. of 70'
> without a permit. I have settled on AN Wireless as my preferred tower
> manufacturer, and their towers are in multiples of 10'. Thus a 60'
tower
> with a mast extending the remaining 10' gives me only 10' within which
> to mount all my antennas -- or less, since I wouldn't want an antenna
> immediately at the top of the tower. All I intend to put up at first
is
> a 3-el. SteppIR (which I *might* perhaps upgrade to a 4-el. later),
and
> perhaps a 2m/70cm beam, so for now that 10' mast is sufficient, but
who
> knows what I might decide to put up later?
> 
> Would it be preferable to get the 50' tower and a mast extending a
> further 20'? The mast would obviously have to be something rather
> substantial (chrome moly?), so there would be little cost saving over
> the taller tower and the shorter mast.
> 
> Have other people wrestled with this question, and what decision was
> reached?
> 
> Note: AN Wireless' surface area/wind loading specs already allow for
the
> antennas being mounted up to 10' above the top of the tower. If I went
> with 20' of mast, I'd mount the SteppIR at about the 10' level and the
> smaller antenna(s) above that.
> 
> Alan AB2OS
> _______________________________________________
> 
> See: http://www.mscomputer.com  for "Self Supporting Towers",
"Wireless
> Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041
with
> any questions and ask for Sherman, W2FLA.
> 
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