Topband: RX 4 square

[Lee K7TJR]

Good Evening Len and all.
   I recognize the statements you refer to as being from my recent 8 element antenna article posted to my website.  First let me say that I cannot speak to the Dx Engineering RX 4 square at all as I have no experience there. I have built a few of my own 4 squares with great results however. The comments about voltage gain and phase shift apply only to my system as described in the 8 element article. The Hi-Z amplifier along with the antenna element mounting arrangement apply a load capacitance to the antenna element itself. This load capacitance is right at 30pf. The antenna element itself in the form of a thin 10 foot element has a source series capacitance of  right around 30 pf. This forms a voltage divider of about .5 to 1. A 6 Db loss. If you increase the length and diameter of the element to 20 feet and about 3/4 inch dia. The series capacitance increases to about 60 pf. This reduces the voltage loss to about 3.5 Db. You also get the extra voltage gain as a result of the longer element. In addition I have modeled this system and found a change in the amplifiers output phase of about 2 degrees going between the two element sizes. These numbers were important to me in the 8 element design however it is my opinion that you would likely see no discernable changes in a simpler 4 square antenna as long as all your elements were reasonably identical. 

73
Lee K7TJR   www.k7tjr.com