[TowerTalk] 40 Meter 4 square tuning

[Dennis W0JX via TowerTalk]

Mike,

Your radial height above ground is a bit on the low side. Four feet would be the minimum, IMHO. Tuning of the verticals is done one at a time, separately, meaning that you can only have one up when you tune it.

Your radials do not need to be a quarter-wave long. See AC0C.com for a very creative solution. He uses three radials, each of which is about 70% of a quarter wave length long. Hence they do not overlap. He makes up for the shorter length by extending the length of the vertical radial until the entire element is resonant.

Also be aware that with a four square, the overall tuned frequency of the array has to be about 5% lower than the "resonant" frequency you want. Mutual coupling between the elements changes the design frequency.

73, Dennis W0JX