[TowerTalk] Reqst for assistance: choosing a remote ant switch
Sat, 1 May 1999 06:22:07 -0400
> Is the Polyphaser strictly a shunt element (gas tube to groundf)? If so,
> perhaps you can place it across the line with a "T" connector and still
> get protection.
It has a series capacitor, but I'd bet money the capacitor does nothing to
help protect anything from lightning damage.
Most lightning problems with coaxial feedlines are caused by
common-mode energy, and in-line protection devices don't do a
thing to prevent that type of damage.
Good grounding and having the common sense to unplug radios
and disconnect feedlines when off the air for a while or when poor
weather is on the way are the best solutions.
But if you want to use a in-line device, I'd use an RCS-8V antenna
switch. When power is removed, the relays open and remove a
shorting bar that ties the input to the output. That shorting bar is
grounded, causing any arcs to be conducted directly to the
chassis. Any differential mode lightning pulses on the coax are
totally stopped by the RCS-8V.
The best solution though, is to disconnect the feedlines and unplug
73, Tom W8JI
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