...and reasonable instrumentation and a good understanding of what is
actually going on. "Difficult" or "hard" is a judgment call from one's
own
particular expertise and experience perspective. Antennas are a wonderful
interest area of amateur and professional radio. Experiment and enjoy.
Read good engineering books if you are interested in antennas.
It doesn't take much instrumentation. When I set mine up, I used a "pinger"
on 1843 kHz. I placed in out a few wavelengths in the direction of the
null, and adjusted the T networks for minimum signal. Because I had
dissimilar antennas, the "T" adjustment was different in each direction.
One element's impedance, the front, generally remains somewhere around what
it was as a single element. Use that element as the common point and do the
equivalent of leading phase to the rear. That would be a conventional T
network, provided the values have enough range. The rear element, if fed
through 1/4 wave of line or the TOTAL of 1/4 wave counting effects of the
feed system, generally is a pretty high impedance (because it is very low
at the element current maximum).
Delay lines would, of course, result in almost no gain or F/B with shunt fed
systems, unless someone deviated from normal procedures and compensated for
the transmission line effects of the shunt system.
73 Tom
All good topband ops know how to put up a beverage at night.
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Topband Reflector
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