Topband: W6SAI three wire inverted L

[Tony]

Hi,
I am about to erect an antenna for Top Band,  I've found an article on the Web from an old issue of Ham Radio magazine, where W6SAI described the evolution of a 3 wire inverted L for use in a small garden/city lot.   The antenna is based on a 135 foot (35 up 100 out) inverted L,  this single wire antenna was adapted to use 300 ohm ribbon, and then to a system with three wires with the centre conductor going to the transmitter and the outer two being connected to ground at the feedpoint.
The claim is that using this system the efficiency of the antenna was raised to over 80 %.

I have to admit to "knowing enough theory to be dangerous",  and it may well be that the much missed W6SAI was correct,  my gut feeling is that this may be another occasion where feedpoint impedance is translated to radiation resistance - can any of you who understand the physics and especially the math please tell me whether I'd be wasting a lot of time and effort making up the spreaders etc for such an aerial with respect to a single-wire Inverted L?

And finally, I tried a rather novel Top Band antenna last Winter KE4UYPs  "Top fed linear loaded" dipole arrangement with 132feet out and 170 feet of linear loading in the other leg at two foot intervals, this enabled me to span the "pond" with 80W and increase my country score quite well,  the downside of this antenna is that if like many of us you share the Antenna space with the XYL who for some strange reason considers that plants should be grown etc, that you can have a real problem with the up and downs of the linear loaded bit... but I mention this as it may be an antenna worth trying for those without the space to erect a full sized Top Band dipole.

I would be grateful for any constructive ideas on the W6SAI antenna

Thanks and good hunting
         Tony G 3 Z R J