> My thought process is this. The 8-circle array uses a
simplified
> broadside/endfire feed to only four (4) of the eight (8)
elements...that is,
> four of the elements are left un-fed no matter which
direction the array is
> steered. I would anticipate that the four unfed elements
would impair the
> gain and FB pattern if left floating. Would they impair
the pattern if they
> were unfed but grounded??
No. Not if unfed and allowed to FLOAT. This means you need a
high impedance at the element.
> The difference in gain and FB is negligible between the
8-circle and the
> 9-circle. But the 9-circles feed system is light years
more complicated and
> perhaps not worth the additional complexity comapred to a
simple BSEF
> network??
The nine-circle also has additional LOSS, so it very likely
has less gain when matching and switching losses are
included. IMO the nine-circle is an example of how a system
evolves when losses are not included and complexity is not
an issue. The G5RV syndrome of the nine element is worth
about +5dB, however.
What is the G5RV syndrome? On 80 meters I blind tested a
G5RV at 100ft against a dipole at 100 ft. Both antennas in
the clear.
1.) When I would call the dipole the G5RV, and the G5RV the
dipole, the ACTUAL G5RV would always win in signal reports.
2.) When I would call each by the correct name, the dipole
would win.
3.) When I would say antenna one and antenna two, they would
randomly tie.
My suggestion would be to install the nine square layout,
and only use the eight vertical feed that excites four
elements. Then you could say it is a nine circle antenna,
and have the same G5RV syndrome along with the better eight
circle performance and phasing system ease.
73 Tom
73 Tom
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