[TowerTalk] Balun in 80m 4 sqr with with vertical dipoles

[Ignacy Misztal]

Does anybody has 4 sq with vertical dipoles K8UR style, with the same tower
used as shunt fed 160m vertical?

I am trying to decide where a balun (or transformer) is needed. An
automatic decision would be to put the balun in center. However, the coax
from the 4 dipoles would be loading the tower at low height, reducing
performance on 160m. So the other option is to put the balun by the 4 sqr
controller on the tower.

I painfully became aware of the problem when trying one vertical dipole
without any balun. Then the shunt feed 160m gained an extra resonance,
resulting in extremely wide BW > 250 KHz. Wide BW is usually indicative of
poor performance.

Ignacy, NO9E