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Tom & Martha Morton wrote:
> In ARRL Antenna Book Ed #18 in the chapter on HF Yagi Arrays, the
> charts show a "Compensator" in addition to the elements mounted on the
> booms. At the bottom of page 11-11, it sez, "Torque compensator
> element is made of 2.5" OD PVC water pipe placed 12 inches behind last
> director." This intrigues me as I have never heard of this. Wanting to
> learn more, I checked the index and could not find anything about
> compensators, torque compensators, or antenna compensators.Will
> someone please direct me to the appropriate reference or please
> explain what this "TC" is all about?
> 73Tom
Hi Tom,
To make a long story short.
The element type of torque compensator was introduced to the masses by
Dave Leeson, W6NL, in his book "Physical Design of Yagi Antennas",
published by ARRL.
Its purpose was to corect antenna torque caused by asymetric placement
of the elements about the mast.
Thanks to Dick Weber, K5IU, we now know that wind on the elements does
not generate forces perpendicular to the boom causing a torque
imbalance. So, we don't need to worry about trying to use an element
torque compensator.
Boom torque compensators are still effective when the mast is not
mounted at the center of a boom.
73, Kurt
--
YagiStress - The Ultimate Software for Yagi Mechanical Design
Visit http://www.freeyellow.com/members3/yagistress/
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<P>Tom & Martha Morton wrote:
<BLOCKQUOTE TYPE=CITE> <SPAN class=300390114-19111998><FONT
FACE="Arial"><FONT COLOR="#000000"><FONT SIZE=-1>In
ARRL Antenna Book Ed #18 in the chapter on HF Yagi Arrays, the charts show
a "Compensator" in addition to the elements mounted on the booms. At the
bottom of page 11-11, it sez, "Torque compensator element is made of 2.5"
OD PVC water pipe placed 12 inches behind last director." This intrigues
me as I have never heard of this. Wanting to learn more, I checked the
index and could not find anything about compensators, torque compensators,
or antenna compensators.</FONT></FONT></FONT></SPAN><SPAN
class=300390114-19111998><FONT FACE="Arial"><FONT COLOR="#000000"><FONT
SIZE=-1>Will
someone please direct me to the appropriate reference or please explain
what this "TC" is all about?</FONT></FONT></FONT>
<BR><FONT FACE="Arial"><FONT COLOR="#000000"><FONT
SIZE=-1>73</FONT></FONT></FONT></SPAN><SPAN class=300390114-19111998><FONT
FACE="Arial"><FONT COLOR="#000000"><FONT
SIZE=-1>Tom</FONT></FONT></FONT></SPAN></BLOCKQUOTE>
<BR>Hi Tom,
<BR>To make a long story short.
<BR>The element type of torque compensator was introduced to the masses
by Dave Leeson, W6NL, in his book "Physical Design of Yagi Antennas", published
by ARRL.
<BR>Its purpose was to corect antenna torque caused by asymetric placement
of the elements about the mast.
<P>Thanks to Dick Weber, K5IU, we now know that wind on the elements does
not generate forces perpendicular to the boom causing a torque imbalance.
So, we don't need to worry about trying to use an element torque compensator.
<P>Boom torque compensators are still effective when the mast is not mounted
at the center of a boom.
<P>73, Kurt
<P>--
<BR>YagiStress - The Ultimate Software for Yagi Mechanical Design
<BR>Visit <A
HREF="http://www.freeyellow.com/members3/yagistress/";>http://www.freeyellow.com/members3/yagistress/</A>
<BR> </HTML>
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