[TowerTalk] Isolating adjacent 4-Squares

[Charles Morrison]

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