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[TowerTalk] tower/rotator woes...

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Subject: [TowerTalk] tower/rotator woes...
From: "Jim Thomson" <jim.thom@telus.net>
Date: Mon, 20 Feb 2017 10:11:14 -0800
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Date: Mon, 20 Feb 2017 17:05:23 +0000
From: Ken K6MR <k6mr@outlook.com>
To: "towertalk@contesting.com" <towertalk@contesting.com>
Subject: Re: [TowerTalk] tower/rotator woes...



Which is exactly the reason you need to torque balance an antenna. If your 
antenna is torque balanced, there will be -zero- torque on the mast in any wind 
condition. If you release the brake and the antenna windmills, you need torque 
balancing.

Properly balanced, there will never be a condition where the rotator cannot 
turn ?against the wind?, because there is no torque generated by the antenna(s) 
for the rotator to overcome.

Ken K6MR

##  I concur.  Fellow across town would destroy his t2X and ham-4  rotors.  He 
has a gross offset on the boom.   So I used the tq comp software on the K7NV 
Yagi stress program, to design the tq comp plate for the REF end of the boom.
He tested the yagi on a smaller  30 ft tower, with no rotor or coax.   It did 
not  wind mill in high winds.   He even climbed up there in a high  wind and 
could manhandle the yagi to another direction, and it would stay put.   So the
software works..as does the same program from DX engineering.   That was years 
ago, forgot all about it.  No more rotor failures as far as I know, but in his 
case, he has pushed the limits of the small rotors to the max. 
Dunno why ant makers dont include the simple tq comp plate, cost nothing to 
implement.  Then like steve sez, if more than one yagi on the mast, alternate 
sides when mounting the yagis. 

##  These days, id still start off with a decent rotor...and tq comp the 
various ants.   If u design the tq comp plate correctly, it requires very 
little tq to actually  turn an ant. 

Jim  VE7RF  

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