>From: Arne Gjerning <gjerning@flash.net>
>
>Been using BIRD Model 74 coax switches which gnds unused antennas for
>years. What are advantages over a switch which does not gnd unused
>antennas?
>
>I am about to build a new ant switch with 11 positions and can build
>with
>either gnding/non-gnding type. Comments welcome.
>
>For info all ants here are monobanders on single tower, 1 radio
>station.
>
>de Arne N7KA
Hi, Arne.
I am assuming you are referring to a tower mounted switch, where the
tower is grounded.
I asked a similar question last year and the consensus was that each
antenna type needed to be analyzed. For example, the standard yagi
with grounded boom and elements should normally be grounded when not in
use.
The complexities come in when you are working with wire antennas. In
some cases, grounding a wire antenna at the top of a tower can have the
affect of putting the antenna in series with the tower. This may or
may not be a problem depending on the RF environment. On the other
hand, just leaving the wire antenna "floating" might also cause
problems. Again, depending on the RF environment.
I am not an antenna expert (though I live fairly close to one ::waving
to Kurt::), so I will leave the discussion of which specific cases to
those on the Reflector who know what they are talking about. But I
thought I would throw this out to let you know that what you asked may
not necessarily be an easy question to answer.
73, Dick
--
Dick Flanagan W6OLD CFII Minden, Nevada DM09db (South of Reno)
Visit http://www.qsl.net/cvrc/
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