Rohn 25G with Ham-IV rotator

Dennis Schaefer W5RZ w5rz@cswnet.com
Fri, 02 Aug 1996 21:16:26 -0500


I am getting ready to install a Ham-4 rotator in a Rohn 25AG3 top section.
The 25AG3 doesn't have enough room in the "open" area at the top of the
section to accomodate the height of the rotator.  The rotator is too big to
push down further into the tower and will not rotate inside the tower except
where the tower sections join together.  

It looks like the best place for it is at the top of the "next to top"
section. The rotator should rotate freely there, but how do I get it in or
out without lifting the top section and the antenna?  

I like the idea of having the rotator 9 ft or so down in the tower.  It
seems that the laws of physics make this spot better than right at the top
for several reasons, but if not, I would like for someone to set me
straight.  (It would definitely make it easier to install a VHF antenna on
top of the HF beam - the small mast for the VHF could just slide in and out
of the main mast).  

I am considering cutting out the bottom horizontal brace on one side of the
top section, then replacing it with a piece of pipe or angle stock with 2
U-bolts. This "temporary" brace could be swung out of the way to install or
remove the rotor.  

This 60 foot tower is house bracketed, and I have two sets of guys, the top
set at 52 feet.  The antenna will be either a 204BA or large tribander, and
a small VHF beam.   

I would appreciate hearing any concerns about this scheme, or better ideas.  

73,
Dennis, W5RZ