Topband: Tower coupling into antenna

[Richard Cariello]

Hello to all,

I am using my tower to hold up a 160 meter inverted L antenna. The wire runs along side the tower from the ground to about 75 feet off the ground. The distance between the tower and the wire is about 15 feet. The far end of the antenna is held up with the use of a tree.

I believe the tower is coupling into the antenna. When trying to tune the antenna by changing the length of the wire this is what I get. At 1.93 MHz I get a very sharp dip in SWR to about a 1:1. Trying to lower the frequency of the antenna I add some wire. The best SWR becomes a 1.5:1 around 1.87 MHz and the dip become very broad.

How can I check if the tower is coupling into the antenna?

How can I change the frequency of the tower so that it doesn't effect the antenna?

Thanks,

Rich AA2MF