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Re: Topband: protect my transmitter from atmospheric discharges

To: "k8gg@voyager.net" <k8gg@voyager.net>
Subject: Re: Topband: protect my transmitter from atmospheric discharges
From: Brad Rehm <bradrehm@gmail.com>
Date: Wed, 2 Jun 2010 11:16:44 -0500
List-post: <topband@contesting.com">mailto:topband@contesting.com>
I agree, George, that a manual disconnect is the best way to avoid
damage.  But I wouldn't consider leaving out the resistor or choke.
One evening many years ago, I was listening on 160 with a vertical
antenna which had no static drain device.  I was unaware that a snow
squal had moved into the area, and each snowflake that hit the antenna
deposited a little electric charge there.  The charge accumulated in
the coax (a long, thin capacitor) and eventually reached the level at
which it could arc across the connector pin and shield, making a
snapping sound I could hear in the shack.

It took a few minutes to realize what was happening and disconnect the
coax from the radio.  The event blew an FET in the front end (easy to
fix).  Since this evening, I've added shunt inductors or resistors to
all of my antenna feeds.

Brad
KV5V

> While I agree that an RFChoke to ground can help
> drain static and a lightening surge protector is also a very good idea,
> nothing outperforms the manual system of disconnecting the coax from the
> radio at the entry point to the house or radio shack.
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UR RST IS ... ... ..9 QSB QSB - hw? BK

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