Bob VE7BS made some very valid points in his previous email. We all get to
hung up on lot's of radials near the feedpoint of a vertical antenna. They
are certainly needed in the near field of a 1/4 wave or shorter L/vertical
but a full wave loop is in a sense a low ground plane with the approximate
1/2 wave horizontal wire acting as two 1/4 wave counterpoise wires. The
highest current is not under and adjacent to the antenna feedpoint but
instead
much further out at a distance that can't be reached by a ground screen.
Also a delta loop is not going to outperform a phased array, especially a
four square,
as the slanting vertical sections are of course to close together and some
cancellation
occurs.
I modeled a full wave squashed delta loop and I'll be glad to email it to
anyone with EZENEC 3.0 that is interested, just email me directly. Actually
I struggled to model it, as I hadn't done to many delta loops recently and
was having trouble getting the dimensions correct. So I went to a fellow
broadcast band dxer, National Radio Club member and expert antenna
modeler/designer, Neil Kazaross from Illinois for big time help. Neil is the
designer of the KAZ receive loop for the broadcast band, a similar antenna
as the K9AY loop.
73,
Thomas Giella, KN4LF
Plant City, FL
Grid Square- EL88wx
CQ Zone 5
ITU Zone 8
Email: kn4lf@tampabay.rr.com
KN4LF 160 Meter Amateur Radio Resources And More:
http://www.kn4lf.com
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