Topband: Inv-L with single elevated radial

[Paul Ferguson]

In Chapter 9 ( (Vertical Antennas) of Low-Band DXing, Section 2.2.4.1 discusses "Only One Radial." ON4UN cites work by Christman showing that having only one elevated radial over average ground has very close to the gain of a quarter-wave vertical using 120 buried radials, but only in the direction of the single radial. It has a 3-4 dB null behind the radial.

The possibility of having 4 radials and connecting one at a time is mentioned.

I am thinking about getting on 160M with an inverted-L and 4 quarter-wave radials elevated 10-15 feet. I would use a relay box to allow attaching any one of the radials at a time or all 4.

If you have any experience with an antenna similar to this, I would appreciate your advice.

Paul
K5ESW
Raleigh, NC