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[TowerTalk] Yagi fixed...

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Subject: [TowerTalk] Yagi fixed...
From: w4an@contesting.com (Bill Fisher, W4AN)
Date: Sun, 18 Oct 1998 17:48:12 -0400

After I took down the offending yagi and replaced it with what was the
lower one of the stack.  I took apart the bad one this morning starting
with the reflector.  Cleaned and tightened everything.  When I got done
doing the tips of the last director, I went to the center insulator to
check the hardware on it.  Problem found:  I had a hairline crack in the
jumper that joins the element halfs.  When the yagi was tilted past a 45
degree angle, the weight of the element caused the shorting strap to make
contact again.  Shorting strap replaced... antenna works again.  

What is really depressing is that I checked all of the straps when I was up
on the tower except the last director.  I figured there was no way the last
director on a 6 element yagi could cause such a dramatic change in resonant
frequency.  Wow was I wrong.  BTW, when I remove the shorting strap in the
AO model of this antenna, it does exactly what I observed.  

Thanks for all the suggestions.

73

Bill - W4AN - K4AAA

Bill Fisher, W4AN (EX KM9P)
http://www.contesting.com 






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