[TowerTalk] Detuning Skirt

[Roger Parsons]

Sorry Dave, I guess I didn't make myself clear.

The tower has never had a detuning skirft on it, but I am considering putting one on. I am aware that detuning skirts are most often used to prevent some other structure re-radiating ones wanted signal as in the case of your towers and AM broadcast stations.

What I want to do is slightly different. My antenna is not the actual tower, but a wire some six feet away from the tower and parallel with it. It obviously couples very strongly into the tower, and it seems to me that the tower is just about the right size to be 3/4 wave resonant on 160m. That is a pretty bad length as (1) it will accept a lot of power and (2) its major radiation lobe will be upwards - not what is wanted at all.

I believe that a skirt with a series reactance can change the resonant point of the tower. What I am very unclear about is how I can adjust it - I believe that normally the skirt is tuned for minimum current in the tower or maximum current in the skirt. I don't think that either of those conditions will necessary be right in my case!

73 Roger
VE3ZI