Four years ago I built a 160m 4 square. I tuned it carefully, had many
1/4 and 1/2 wave radials underneath each vertical and with 1.5kw into
the array didn't measure anything into the termination at 1.83Mhz. When
I went to use it though, all the stations were 90 degree off, Europe was
best to the SE, Japan to the SW it drove me crazy. I asked everybody
with no avail. I worked on it for a year and finally switched it over to
a Parasitic array and have had great success.
This summer I built up a 80m 4 square inside the 160m array. I did
everything to the book, carefully tuned it, layed down 40 1/4 and 40 1/2
wave radials under each vertical. But agaian as with the old 160m 4
square everybody was 90 degrees off. Well, last week I heard Tom, W8JI
chatting so I broke in and told him my story. At first he didn't have
any idea until I told him that I used 3/4wavelength 75 ohm transformers
to reach two of the verticals instead of the typical 1/4 wave
transformers. That was it he said, he told me to make all four verticals
symetrical by added 1/2wavelength of 75ohm of coax to the verticals with
only 1/4wave transformers on them. It appears that when I had
3/4wavength transformers to two of the verticals I had a phase reversal
and that was causing my problems! I did the exact same thing four years
ago on the 160m 4 square. Let me add that the 80m 4 square really works
well now. I'm getting 25-30dB F/B and the array is always 2-3 S units
better than my single 1/4 wave vertical 200 feet away from the array.
Now my only problem is should I tear up the 160m parasitic array in
favor of the 4 square? I'll have to pondor that for a while. Thanks
again Tom! You made me one happy man!
Peter
W5PS
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