[TowerTalk] PST61 Rotor Reliability?

john at kk9a.com john at kk9a.com
Tue Dec 12 07:55:59 EST 2017

That is the way it appears to me also, however I am not a mechanical
engineer.  The only time I have seen any issue with same side mounting was
at my P40A station. I had a heavy homebrew 20m beam and a 2el 40m on a 2
1/2 diameter aluminum mast and the weight on one side caused a very slight
bending of the mast. From the ground it was not noticeable and I never had
a rotator issue. A steel mast would have bent significantly less.

John KK9A

To:   <towertalk at contesting.com>
From:	"Gary Schafer"
Date:	Mon, 11 Dec 2017 20:34:23 -0600

I have from time to time seen it professed that mounting two antennas on
opposite sides of the mast will equalize the torque supplied by wind.

The only thing mounting on opposite sides of the mast will do is equalize
GRAVITY forces on the mast (that try to bend it over) which will be rather
small differences given only a few inches distance apart.

Torque is rotational. Both antennas are going to exert the same amount of
torque no matter which side of the mast they are on.
What am I missing here?

Gary  K4FMX

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