Date: Sun, 1 Sep 2019 22:26:39 +0200 (CEST)
From: "dj7ww@t-online.de" <dj7ww@t-online.de>
To: "towertalk@contesting.com" <towertalk@contesting.com>
Subject: Re: [TowerTalk] High VSWR
Jim,
You did not mention before that the installation of a vane becomes necessary
when you mount the boom at it?s center!
## vane NOT required if boom mounted at center. Counterweight IS
required....at light end.
With the boom just mounted at it?s center, the wind pressure on the boom will
be much higher on the side with the longer elements whatever counter weight you
place on the side with the shorter elements and cause turning force on the
antenna..
## Longer eles... and number of eles has nothing to do with with it.
Each ele is symetrical...so the eles are already tq balanced . If
wind hits the eles at an angle...... and viewed from above... left
side of eles bends CW.....
meanwhile right side of ele bends CCW...... they cancel out...... or
vice versa. The eles are still tq balanced.
## I tried this experiment. 40 ft boom..... mounted at exact center
of boom....to mast. Only ONE 20m ELE USED...THE REF..... mounted of
course, at extreme end of boom. no counterweight used for this test.
No coax, no rotor.
Does not rotate, nor ....weathervane, etc. Stays put, regardless of
windspeed, or where boom was oriented by hand.
Jim VE7RF
<73
<Peter
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