Topband: Shunt fed T

[Gary Hinson]

> Could anyone advise me about top loading when 4 wires are use 
> as an alternative to 2 with this type of antenna. 

John,

Though I am no expert, I think you are on the right lines.

The Tee-top, or X-top, or disc-top, or self-supporting top-hat are all, to my mind, working as
"capacity hats".  As with earth radials, I suspect "more, shorter" beats "less, longer" wires, part
of the reason being less reduction of the vertical height as you say.

There may be some formulaic method of working out how long the top loading wires must be, but I
guess an antenna analyser and a few hours in the field to trim and measure will eventually give a
good match on your frequency of choice, in your specific location (since interaction with nearby
objects will no doubt affect the exact values needed).

73 GL,
Gary  ZL2iFB