Re: [TowerTalk] EHS leads for Phillystran

[john@kk9a.com]

I am not sure how you know that the pattern was distorted but I think  
this is a good practice Tim. My top homebrew 15m beam has a higher SWR  
than the lower two - 1.4:1 vs 1.1:1.  Just below the top antenna is a  
Rohn 65 massive star guy bracket with six Phillystran Big Grips  
directly attached.  Perhaps insulating the guy would help.
John KK9A


Tim Duffy k3lr at k3lr.com

I had a problem with just Preforms attaching to the tower legs connection -
which caused distortion in the pattern of close mounted Yagi's. That is,
Yagi's that were mounted only a few feet above a guy connection point. The
VSWR of the affected Yagi would change with rotation and the effect of three
Preforms connected to the tower was confirmed with modeling. The solution
was to use a bent pin shackle and an insulator right at the tower
connection. You can see it in this view of the middle four element 40 meter
OWA Yagi stack at K3LR:
http://www.k3lr.com/2016/ring.jpg

Using insulators at the tower connection completely solved the pattern
distortion and VSWR changes with rotation.

73
Tim K3LR

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