Another low cost method I have used is to route the control cables
through a section of conduit near the base of the tower. 10 to 20 feet.
Make two 90 degree bends; one bend perpendicular to the tower and the
other bend towards the shack. Ground both ends of the conduit-at least
one end to the tower. Before your control cable enters the house, make
a double knot.
The double 90 degree conduit and the double knot adds inductance to the
control cable path. You can still add the surge protectors on the cable
before it enters the house-but I have not found this necessary for my 70
foot tower in S.E. Michigan.
Carl, NW8Z
Ps I put double knots near the outlet in all the power cables to my
indoor electronic equipment: Ham radio, TV, stereo, refrigerator etc.
The double knot creates a complex inductance -suppressing lightning
surges on the AC cord to the equipment.
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of
john.brewer@us.schneider-electric.com
Sent: Tuesday, March 23, 2004 4:07 PM
To: towertalk@contesting.com
Subject: [TowerTalk] Protection for control cables.
A couple of alternatives come to mind re: protecting SteppIR cables
without hocking your first born.
1) Put a Molex-type connector at the bulkhead, and disconnect when
not in use. (Which is what I do with my rotor cables)
2) Investigate building your own shunting interface. The MOV's and
gas spark gaps are available as components. and are
well characterized. I'm not sure about the Polyphaser brand
but I believe the Alpha-Delta transitraps are all gas spark
gap technology.
73,
John K5MO
PS: I've visited the Langmuir Lightning Research Center in S.Central New
Mexico, and been in their "block house" from which the wire trailing
missles
are fired (it actually is under the launch pad, as I recall).
Fascinating and beautiful place! Man, do I miss NM!!!
_______________________________________________
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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