> The latter phenomenon has me wondering -- perhaps ~150 degrees length
> of coax doesn't load the reflector dipoles enough for optimum F/B at
> the resonance of the driven dipole, but the added coax length required
> to optimize the reflectors imposes too much additional loss.
Since you basically want to short the unused dipoles, it would
make sense to use an open 1/4 wl line (if the relay could stand the
voltage). However, I really prefer feeding all the elements because
the SWR on the transmission lines is MUCH lower and the
antenna is more efficient.
There probably are a dozen ways to do this, but if you properly
decouple the shield every case would allow you to ground the
shield and leave it grounded at all times.
Why don't they build this array with 1/4 wl electrical lines?
73, Tom W8JI
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