I would appreciate some help with my 160m receive 4-square antenna. It has
horrible directivity which I presume means that I have the phasing or
amplitudes wrong.
The array consists of 4 passive vertical antennas, spaced quarter wave across
the sides, each 25' high and top-loaded. Each has 8 50' ground radials, is
resonant on 1850 kHz and is loaded to 75 Ohms - all exactly as W8JI. I am
confident that this part of the array works properly.
There is a pdf copy of the schematic at:
https://www.dropbox.com/s/2wg3kj9r42woqbi/Vertical%20Array.pdf?dl=0
Ignore the excessively complex control circuitry - that bit also works fine!
I sum the two middle elements with a two way hybrid combiner, and the middle,
front and rear elements with a three way hybrid combiner. These are commercial
units and are claimed to have excellent phase and amplitude balance. The only
real difference (I think) between my circuitry and other published designs is
that the two way combiner allows me to use a single 75 Ohm phasing cable rather
than two in parallel.
So what have I done wrong?
73 Roger
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