I have used 4 bi-direction 760 foot Beverages for 5 years or so here in
Michigan.
I put up the AS SAL-30 a month ago and my experience with the has been very
favorable.
I can't do a direct A to B with the Beverages right now so I must reserve
making any bold statements about the comparative performance as yet, but it
definitely beats a full size 4-Square on 80M.
Modeling indicates that if single band (160M only) performance is desired -
it can be optimized even further from the broadband 'tuning' I am using at
present.>>>>
QEX has an article on this antenna, and it is republished on the Antenna
Specialties website.
Is is a two element crossfire vertically polarized array made from loops.
Personally, if I were going to build one, I would spread the loops apart. I
would make the loop centers as far apart as possible, not to exceed 1/4
wavelength on the highest band.
The directivity should be very similar to a properly designed and
functioning four square, although near field coupling in congested
installations could make a larger element four square, or a larger array,
more noisy.
When I was fighting LORAIN on 160 and wanted to work Japan (for Asia), I
built an open wire line coupled array of eight loops like this. The loops
were 70 ft on centers. This, and a good noise pulse blanker, allowed me to
work JA1HKP and JA7AO on 160 through 100 kW.
My long array loop design was a offshoot of looking at an advertisement for
a loop array sold by some commercial company for the military. If they could
do it I could figure out how I could do it.
My noise pulse blanker was a offshoot of a LORAIN blanker concept of a W6
published in the 1950's (I guess). I just used a different circuitry of my
own style, and added a delay line so the blanking pulses appeared on the
switch tube (I originally used a 6BE6, and later changes to those new
devices called semiconductor diodes).
The log-loop array allowed me to hear only one or two LORAIN signals, so
blanking time when signals were blanked decreased.
I probably spent 400 hours so I could work two JA stations.
73 Tom
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