Date: Fri, 16 Jul 2010 10:02:56 -0700 (PDT)
From: Terry <ab8al@yahoo.com>
Subject: [TowerTalk] Antenna loads for rohn 45
Can anyone tell me what kind of antenna load I can stack on Rohn 45?
I am looking at 130' of tower with a 4 element (full size) 40 Meter at the 130
foot mark but would like to stack 6X6 60ft boom
20 meter antennas one at 135 the other at 73". The phyllistran guys would be at
43 86 and 129 more or less. Would adding a
4th set of guys make a difference? then the would be at 32,64,96, & 128.
Replay to ab8al@yahoo.com.
Thanks,
Terry
## Instead of a heavy duty rotor to turn the top 2 x yagis.. + 2 x heavy duty
3" thrust bearings, plus 3" heat treated chromolly mast, + mast steps
... plus a TIC ring [ with 2 x motor's] to turn the bottom yagi , another
option would be to use K0XG rings.. and just rotate the entire tower !
## Then you could easily have 10-20' of tower above the top ring. If you go
that route, you are better off to use 55-G,
or 45-G with the solid legs. A friend just installed 190' of 55-G.. using
4 x K0XG rings.... and has 25' of tower above the
top ring. I found from the hill radio catalog, that rohn also makes ..'HD'
45/55/65 G sections. These sections are DOUBLE braced,
and are crossed in a ...'X' . So you end up with not only the normal .."Z"
bracing, you also have an "X" . The 55-g-HD sections are heavier,
138 lbs vs 100 lbs for normal 55-G. My friend used 3 x of these HD
sections at the very top of the tower, from 160-190'. The top
ring is at 165'. The K0XG rings are unique. they can be mounetd anywhere
along the section... not just at a section splice point !
## Rotor is massive.. and sits on the base pedestal. You can turn as many
yagi's as you can fit on the tower. In his case, 14 x yagi's in all will be
installed along the length of the 190's of tower. 4 x sets of 3/8"
polygon guy wire are used. The new guy anchors used are 10.625" steel tubes
in a 5 x5 x 5 block of cement. Inside of each anchor tube is also full of
cement. A rectangular steel plate is welded vertically to the 10.625" tube.
The 3 x new anchors are 170' out from the base of the new tower.
## the only drawback to the rotating towers... is everything is pointed in
the same direction.
## His previous set up consisted of 160' of Rohn 45-g... and had 7 x yagi's
on it. A pst-61 on top.. turning a 40m yagi, with the 20m yagi above it.
4 x tic rings turned 5 x more yagis.
Later.... Jim VE7RF
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