Bob, for a good understanding of the concepts of phasing in these RX antennas,
read Chapter Seven of ON4UN's "Low Band DXing." The length of the delay lines
primarily affects the placement of the nulls of the array while the voltage
output of the antennas and amplifiers controls the depth of the nulls. The more
perfect the balance of the output of each antenna and amplifier, (i.e.,
equal), the deeper the nulls. That is why when conductors interact with the
elements, the pattern gets screwed up. They mess up the balance of outputs of
the antennas. The spacing of the antenna elements is generally optimum on one
band. If selected for 160 meters, the 4 SQ pattern deteriorates as you go up in
frequency since the spacing becomes wider electrically. At 30 meters, there is
practically no pattern although the array hears very well. As far as phasing
relationships, the HiZ antenna system uses "Cross Fire" phasing, an approach
that maintains a balanced
relationship in the delay lines over at least a 2 to 1 frequency range, so
that the system works very well on 160 and 80 meters.
73, Dennis W0JX/8
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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