We have our share of lightning and 'canes here too (Houston area). My tower
is only 150 and will soon be adding two more at 150 and 160.
I have found the most effective protection is a well-designed single point
ground system. This includes a connection to the AC mains entrance ground.
I also use Polyphasers in the bulkhead (8 so far) but have had lightning
damage through them in the past without a proper single point ground. I
also homebrewed a relay box for the shack that disconnects and grounds the
antennas and equipment AC connectors when the power is turned off. The
ground for this box and all other shack equipment is a Harger copper bar
that connects to the bulkhead and single point ground in the yard.
73, Keith NM5G
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Cqtestk4xs@aol.com
Sent: Thursday, September 01, 2005 1:04 PM
To: TOWERTALK@contesting.com
Subject: [TowerTalk] Rain static, lightning and Polyphasers
Having the biggest station in the lightning capitol of the US, I am pretty
well qualified to talk about lighting hits and such.
For years I, and lots of my buddies in the FCG, have been plagued by
lighting hits. All of the big stations with towers 100 feet or more have
been hit, sometimes multiple hits.
Three years ago, I tackled the problem in earnest. Among other things, I
redid a bulkhead in the wall now contains a wide flat piece of copper to the
grounds. But the biggest improvement I made was to install Polyphasers on
all incoming coax lines. With twelve lines, it was a big investment.
In addition to doing the above, I use quick disconnects on the coax coming
from the bulkhead, and quick disconnects on the control cables coming from
the bulkhead. All lines stay disconnected unless I am on the air including
the power cables. Also, I disconnect the cable Internet connection, by
quick disconnect, when lightning is heard.
These measures may sound like overkill, but even though I am the heart of
the thunderstorm capitol of North America and have three 200 footers, I have
not sustained any damage in the last three years....a record for me!
By the way, a couple of weeks ago my brother's sailboat, ten miles away from
here, took a direct hit while it was anchored next to his house. He now has
about $7000 worth of electronic goodies which he can now use as emergency
anchors, including a very nice Kenwood rig. Luckily, he was not on the boat
when it was hit.
Bill K4XS (in the land of lightning and 'canes)
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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