[TowerTalk] Please Help Me Decide on a Tribander or

[Jim Thomson]

Date: Thu, 18 Apr 2013 17:06:28 -0400
From: Wayne Willenberg <wewill747 at gmail.com>
To: towertalk at 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