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Old November 13th 07, 06:44 PM posted to rec.radio.amateur.antenna
Denny Denny is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 326
Default Active receive 4 square and others

In doing some study of active receiving antennas I see in a couple of
white papers on the subject that the author determined he needed a
specific phase shift between one or more of the elements and the
combiner, such as 110 degrees, so he proceeded to cut a specific
length of coax determined by it's velocity factor X the desired
fraction of a wave...
This is one of those things that you always accept at face value in a
published work, but this time my doubting side kicked in... We know
that simply inserting a nominal electrical length of coax - such as 90
deg or 180 deg - into phased transmit arrays does not work as planned
most of the time due to mutual coupling... I have read the
contributions of Roy and Al Christman, et. al. on this not
intimating that I understand it...
Anyway, in shortened, loaded, active amplifier, receiving arrays can
one simply insert a nominal number of electrical degrees of phasing
line as the mathematical model calls for, or is their more to it...
Hoping that Roy, AL, or Walt, or others will chime in here...

denny / k8do