Copied from Dr_DX's post.
Quote from earlier post:
Lightning Antenna's Quads use the same matching system that SE called the
SFS FEED SYSTEM. It allows the SWR adjustment close to the point where the
antenna mounts to the mast.
It consist of flexible wires (not coaxes) running along the boom and also brass rod stubs,
which are included with our set of wires. The SFS System allows the use of much more
power than a Gamma Match and results in very low SWR over all forty channels.
Take a look at the Patent here:
Patente US4236160 - Loop driven element antenna system and voltage feed system - Google Patentes
SFS provides two independent feed points, one pure vertical
polarization, the other purely horizontal. Two coaxial lines
then run to the operating position as usual and are selected by
the operator through a coax switch. (Neither the antenna switch
nor these coaxial lines are included with the antenna.)
In a nut shell the antenna is voltage fed and NOT current
fed like a traditional quad. That what allows this
antenna to be dual polarity.
I hope this answer your questions.
Thank You for interest in our antennas.
George.
Lightning Antennas
Manufactured in CA by INNOVA
Tecate, CA 95117
(408) 625-7717 Phone
(408) 457-9440 Fax
george@lightningantennas.com