[TowerTalk] Isolating adjacent 4-Squares

[john at kk9a.com]

Did you model this before building it?  From the little bit of  
vertical array modeling that I have done I found the patterns easily  
skewed by other verticals and towers, even those pretty far way. You  
may have been better off centering the 160m 4Sq around the 80m one.

John KK9A


Charles N1RR wrote:

I have an 80M wire 4-square around tower #1. (90ft with two big 10M & 15M
monobanders) Each vertical has 12 above ground radials and is tuned to
3535. All guys are broken with insulators.
This array works well.

My second version of a 160M wire 4-square around tower #1 was raised last
week. They are Inverted L's  to a 120ft tower. It already has two Cushcraft
40-2CD's and a big homebrew 20M6L OWA yagi. All guys are broken with
insulators. Each Inverted L has 20 on-ground radials and is tuned to 1725.

The closest 80M element is 40 feet from a 160M element.
The 160 is not working well. I will be testing the phasing lines once this
snow melts. ###

I want to apply a passive device to further isolate these systems. I'm
thinking of a 1/4 wave 50 ohm shorted coaxial stub on each feedpoint. My
first guess is the 160 elements.... ?

Alternatives are to move one of the arrays.... but I'd rather explore
making them work where they are.
-Charlie N1RR