[TowerTalk] Reqst for assistance: choosing a remote ant switch

Tom Rauch W8JI@contesting.com
Sat, 1 May 1999 06:22:07 -0400

Hi Mike,

> 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 
the equipment.


73, Tom W8JI

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