[TowerTalk] [SteppIR] boom balance

[paul@w8aef.com]

One of the magazines (73?) ran a life test on rotators many years ago.  The 
test consisted of mounting the rotator horizontally, installing a 10' mast, 
and hanging a cement block from the far end of the mast.

Then run the rotator back and forth through it's full 360 degree rotation as 
you count the (one way) turns until failure.

This was back in the days when the Ham-M was king, and I recall it winning 
the contest.

I seem to recall the first rotator failure, not Ham-M and I cannot remember 
who, was less than 5 turns.  I think the Ham-M went to almost 100 turns 
before it failed.

If I were to side mount an antenna I would go with a barn door.  The mast 
for the rotator maybe 5 feet long, the rotator at the bottom and a thrust 
bearing at the top, mounted on standoffs from the tower by 12".  Make a 
'door' out of a couple of pieces of UniStrut 18" long, one end of each 
UniStrut U bolted to the mast, the other end of the UniStrut U bolted to a 
secondary 3' mast.  The antenna would mount in it's normal fashion to the 
secondary mast and a diagonal reinforcement from the near end of the upper 
UniStrut to the far end of the lower UniStrut to take the weight of the 
antenna.

And if the U bolts slip and the mast tilts, back up and make a welded 
assembly.

Or get a quantity purchase on rotators.

de Paul, W8AEF


----- Original Message ----- 
From: "Al Williams" <alwilliams at olywa.net>
To: <towertalk at contesting.com>
Sent: Saturday, October 01, 2005 2:20 PM
Subject: Re: [TowerTalk] [SteppIR] boom balance


> How important is it to balance the load on a rotator and which rotator is 
> best able to withstand a completely one sided load?