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Dear LF enthusiasts and antenna experts,

I am planning to re-engineer my antenna during the Spring, and I have a design decision to make.

I use an "L" antenna with a vertical section and a horizontal top section that is 20m long. The "horizontal" top section is 10m high at the house end, and slopes down to 5m at the far end. The vertical section is a single wire, with a large loading coil/variometer at the bottom, in the usual time-honoured fashion.

My choice is:- do I feed the top section at the house end, in which case the vertical section will be 10m high, or at the far end, where the vertical section will be only 5m high? At first glance, it might be thought that the 10m vertical would be preferable, but the fact that the top section slopes confuses the situation.

Another problem with feeding at the house end is that the vertical section is very near the house and causes all sorts of RFI problems. It also picks up a load of mains-borne rubbish!

Second question:- Has anyone experienced any tangible benefits by including an extra loading coil part-way up the vertical section?

All replies gratefully received!

73, Dave G3WCB IO91RM