While Mr. Leeson's book ("Physical Design of Yagi Antennas") is
very informative, he is unfortunately incorrect in his analysis and
comments on torque compensation (chapter 6). There is no need
for dummy elements. The correct way to torque balance an
antenna is described by Dick Weber, K5IU, in several articles that
appeared in Communications Quarterly ("Determination of Yagi
Wind Loads Using the 'Cross-Flow Principle,' " Spring 1993;
"Aerodynamic Balancing: Part 1," Summer 1994; and "Aerodynamic
Balancing: Part 2," Winter 1995).
73, Arliss W7XU
----------------------------------------------------
On Fri, 22 Nov 1996 09:35:42 -0500 K7LXC@aol.com writes:
>In a message dated 96-11-21 22:49:11 EST, you write:
>
>>I have heard that someone has discovered how to WIND balance this
>antenna by
>>adding plastic sheet to the boom at the appropriate spot.
>>
>>Does anyone know how to do this or have the needed information or any
>other
>>ideas on how to solve this problem?
>>
> The father of this technique is Dave Leeson, W6QHS, and it is
>discussed
>in his excellent book, "Physical Design of Yagi Antennas". The
>technique is
>called "torque compensation" and is well covered in chapter 6 of his
>book.
> You basically add a dummy element of PVC to balance the wind load.
>
> BTW, a better place to ask a question like this is TowerTalk, the
>tower
>and HF antenna reflector. Send a message to
>towertalk-request@akorn.net with
>subscribe in the message and you'll get signed up. Lots of
>interesting
>questions and answers available there.
>
>73, Steve K7LXC
>
> TOWER TECH -- professional tower supplies and services for
>amateurs
>
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