[TowerTalk] "Magic" length from tower to first insulator

[Steve London]

First of all, 10 to 13 feet guy wire length, before adding the first 
insulator, would be absolutely the worst thing to do if you have a 15 
meter antenna in the vicinity. Think about it - you have created a 
resonant 1/2 wavelength 15 meter element consisting of two 1/4 
wavelength wires, interconnected by the tower section.

I recently wrote an article, published in the Novemeber/December 2015 
NCJ, on the subject of modeling and choosing guy wire lengths. It 
partially debunked the old table in the ARRL Antenna Book of "good" guy 
wire lengths.

73,
Steve, N2IC