On 4/8/2020 12:28 PM, Lee STRAHAN wrote:
What I do know about that also is mathematically those 8 elements theoretically
can produce an RDF of right at 16 dB. The rub is the element amplitudes and
phasing has to be controlled to some remarkable unobtainable accuracies to do
that. Just maintaining 2% amplitude accuracy and 1 or 2 degrees phase stability
10 years ago when the 8 array was put into production was all I thought I
could squeak out with the then current components and measuring ability I
could a
fford. Buying 1% resistors and capacitors in surface mount is now common
which has helped available accuracies and my test equipment is much better than
I had at the time. Chasing these things is part of what I do trying to push the
barriers of low band Receiving.
Filling the gaps, nulls in a pattern are the result of cancellation of
multiple signals from two or more antenna elements. Cancellation is
maximized by very precise matching of amplitude AND phase; small errors
in either result in less cancellation.
73, Jim K9YC
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