On Thu,10/29/2015 12:02 PM, K5WA wrote:
Has anyone got a solution that they've used successfully at a frequent
lightning remote site?
This discussion came up this week on the Topband reflector. Study what
W8JI has to say on the topic. Also study my material on bonding and
grounding. He and I are in complete agreement -- bonding is far more
important than grounding (and both are important).
Here's my take on it. http://k9yc.com/GroundingAndAudio.pdf
Understand these fundamental concepts.
1) EVERYTHING in a premises must be bonded together. Separate grounds
not bonded to others are a CAUSE of lightning damage. The principle is
to allow everything in the premises to rise to the same (high) potential
at the time of the strike.
2) NEVER use shunt mode surge protectors on branch circuits. They are a
CAUSE of lightning damage. As an alternative, use either a "whole house"
protector at the service entrance, and/or SurgeX series mode protectors
on branch circuits.
3) All antennas should be coax-fed, with shields bonded at a common
entry point, with that point bonded to all premises grounds. That puts
the shield at ground potential. Use an feed-through arrestor on each
coax to short the center conductor to the shield. This limits the
voltage at the RX input.
4) Carefully bond together the chassis of every piece of gear on your
operating desk using short, fat copper. Bond from chassis to chassis in
parallel with any audio and control cables running between them. This
prevents a strike from exciting Pin One Problems, which would otherwise
likely cause damage. Virtually ALL ham gear has Pin One Problems on
audio and control connectors, including Elecraft rigs.
Here's an K3-specific trick that K6XX told me about. Use Ant2 for all
bands, with antenna switching external to the radio. When you shut down
the K3 (by turning them off, NOT by killing power), it will connect Ant1
to the radio, to which nothing is connected.
73, Jim K9YC
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