[TowerTalk] 75M Rotatable Dipoles

[n4kg@juno.com]

Jerry,

A 75M rotary dipole parallel to the Yagi Booms is the best
way to prevent interaction, ignoring the total wind load.
You may still be able to get away with it because you 
need to calculate the wind load of the Yagi elements
for head on winds and the booms (plus 80M dipole) for
winds perpendicular to the booms. Whichever one is
greater is the worst case.

Interactions with 80M inverted vees can be 'controlled' somewhat
by changing the feedline length / termination (short / open) or
by using a tuner on the inverted vees and adjusting for minimum
interaction on the Yagi's.  This may require different conditions
for each of the HF bands.

Do you have room to hang a rope supported 80M 4 square 
around the tower?

Tom  N4KG


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