I forgot to mention that each 20' vertical element had a top hat made up of
three 20' down sloping wires terminated with insulators then tied off to
ground stakes to guy each element. As I recall is took about 34 mh to
resonate the elements at 1825 KHz. Some additional series resistance
brought the total impedance to 50 ohms. I used 50 ohm coax because I had it
on hand...75 ohm would be a better choice, yield better bandwidth, and make
the whole array a little more tolerant of element impedance variations. The
performance of my array was good...on par with my 600' two wire Beverages.
73...Dave
W0FLS
About five years ago I built the short vertical array designed by Tom, W8JI.
I believe this was the first time the design had been built. Tom, as
always, was very helpful in getting the array optimized. I believe that
same design has become used by DX Engineering. I used 20' vertical elements
with 100' spacing (141' diagonal). I used 6 each 60' radials on each
element.....
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