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<DIV><FONT size=2 face=Arial>Dave,</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>Give thought to what happened. I know 42 inches
probably probably means a lot to you and I can understand that. You have
determined the weak point in the system. If your mast was steel, continued
flexing softens the metal at the flex point. Aluminum becomes brittle with
flexing (work hardens). If you leave it where it is, you may not have to worry
about wind. Model the antennae to see what the decreased gain is. Maybe you
don't want to go back to the full 42 inch difference. There is a gain to be
achieved in never having to worry about wind and ice load and wind. My antennae
are not as high as they could be, but ice and windload or wind have never been a
worry. My three element 6 M beam is set up with a very crude slipping clutch so
that all the mast and rotor rotate if the wind really gets a hold of it. This
way a component of the energy that might bend the mast or damage the antenna
gets translated to a rotational component. I have to rezero rotor every so
often, but that is trivial. Over the years, I have heard some strange creaking
and groaning, but have not lost an antenna or had damage since I have been
licensed. On the flip side, my stuff is not as effective as if I pushed the
envelope. But physics and gravity will always win!</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>George</FONT></DIV>
<DIV><FONT size=2 face=Arial>N1YAE</FONT></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="FONT: 10pt arial; BACKGROUND: #e4e4e4; font-color: black"><B>From:</B>
<A title=k1fsy@vhfwiki.com href="mailto:k1fsy@vhfwiki.com">David McKenzie</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=450@lists.vhfwiki.com
href="mailto:450@lists.vhfwiki.com">144.450 Mailing List</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Wednesday, November 24, 2010 12:23
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [450] the wound! (i mean
wind)</DIV>
<DIV><BR></DIV>The mast on the HF tower bent just above the thrust bearing in
last night's wind. I dropped it down and cut the mast just above the bend. The
HF beam and loops are now 42 inches lower until I can replace it.<BR><BR>The
bend was very slight but was more than enough to bring the top about 30
degrees off vertical.<BR><BR>No other damage here.<BR>
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