Topband: Shunt feed bandwidth & coax

[Kenny Silverman]

Hi All,  

Thanks again for your help back In December. KC4D’s 135’ tower (110 degrees electrical length) with an omega match is up and running. There are 60 110’ radials though half go out 40’ and are coiled up until permission is arranged to go on neighbors land. The shunt is a 4 wire cage with 8” spacing and about 30” from the tower.  Modeling indicates the 1.5:1 bandwidth is close to 100 kHz and that is seen in real life

Q1:  does that bandwidth seem ok?  I’ve heard of other tall towers where the 1.5:1 bandwidth is 50khz. I’m concerned there some loss based on the bandwidth 

Q2:  the coax and roter cables for the tower yagis are run inside the tower. Does anything need to be done to the coax coming out at the base such as putting chokes on, or grounding the coax to the tower at that point?  Right now neither are being done

Q3: one of the yagi feedlines is long and coiled up outside the tower at the base.  Is that an issue?

There is a definite increase in performance compared to the N4KG feed being used before. I just want to make sure we’re getting peak performance. 

Regards , Kenny K2KW