Thread: Yagi plans
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Old January 26th 05, 03:52 PM
 
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Jim - NN7K wrote:
wrote:


If i use a conductive boom and ground it, is there no need for a
coaxial lightening arrestor?

I wouldnt plan on avoiding lightning protection, just by useing a
conductive boom, nor for that matter, even loop (electrically short
circuit to DC) feed for ANY antenna! When lightning strikes, it is
going where ever it wants to, in spite of the best grounding

intentions
Remember, that if lightning can travel a mile, in open air, it will
go where it wants when it hits an antenna! tho the bulk of the

energy
will disperse to ground, there is always SOME thjat will go down the
coax , even in a close strike! And whan that happens, dammage will
occur, especially without protection. I remember working on a base
station during a storm, haveing removed an antenna- the coax was some
1 inch from the edge of the base station, and produced a spark (Ill
let you figure the voltage at that point) , and that wasnt even a
direct hit-- the strike occured some 3-4 miles away! Look at it like
an insurance policy- 50 to 100 bux is cheap when talking about
replaceing a FT-847 (or other expensive rig). "Course the best
protection would be disconnect the radio, and ground the coax. But
then there is still no garentee. Jim NN7K


Is it possible to make a coaxial surge supressor? Are there still plans
that use a metal boom? What about static electricity?