At 12:50 PM 8/13/02 -0400, KI7WX@aol.com wrote:
>Many of us view this as a feature because without modification the RCS8V
>is readily used in phasing circuits for two yagi stacked arrays, and in
>low band setups like the K8UR / K3LR vertical dipole arrays which require
>open rather than shorted lines.
Half correct, I think. K3LR says in the QST article on this array --
actually first used by W9LT as far as I can find out -- that BOTH the
shield and the center conductor of the coax feedlines must be floated in
order for them to properly function as loading for the reflector function
of the undriven elements. If I'm not mistaken, the K8UR article also shows
a switching system that floats all unused shields AND center conductors.
A point I don't think anyone has yet made this time is that there may be
circumstances in a given configuration of antennas on the tower where
either a shorted or an open configuration may be desirable, to achieve
needed detuning of antennas not in use, to avoid interaction. I think K6LL
has commented on this as a way to detune a 40-meter yagi to avoid
interaction with a tribander on the same tower.
73, Pete N4ZR
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