Date: Thu, 18 Apr 2013 17:06:28 -0400
From: Wayne Willenberg <wewill747@gmail.com>
To: towertalk@contesting.com
Subject: [TowerTalk] Please Help Me Decide on a Tribander or
Monobanders
My 86 or 89 foot crank-up tower project seems to be progressing through my
County review boards. So now I am getting really excited for my first
tower.
## whoa, stop. WHICH crank up tower are your talking about ?? Monobanders
on
a 15’ mast will DECREASE the windload rating of the tower, simoly cuz you have
now
made the tower 15 feet taller, do the maths. Your 89 foot tower now becomes a
104 foot
tall tower.
## what you achieve with monobanders, you will lose right away with
interaction.
You will also have one helluva time trying to get at the ants that are further
up the mast, or
trying to pluck them out.
## a 20-15-10 m tribander or 5ba, etc would work good, then put a 40m shorty
dipole at the
top of the mast, turned 90 degs.
## Think this through real carefully, or you will kick yourself. Stacked
monobanders on a 15 foot
mast is a pita..... plus you are gonna need one hell of a good rotor...and a
t2X won’t cut it. You need
BIG if you want to turn stacked monobanders. Don’t mess with a 2 inch mast
either, too small, use a
2.875 inch x .25 inch x 90 ksi DOM mast. The 2.875 x .25 mast weighs the
same 140 lbs as a
2 inch x .375 inch mast.... yet is a helluva lot stronger. All this weight
piles up.
## a simple multibander just above top of tower eliminates the heavy mast.
A good 40-10m yagi
would be the real ticket, albeit expensive, which gets offset since you don’t
need a huge heavy mast.
With a yagi just above the top of the tower, you can use anything for a mast.
Jim VE7RF
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