Topband: More - lightning protection on 4 sq

[David Raymond]

Greetings everyone. . .

I received several responses to my email regarding installation of lightning protection on my 160 meter four square.  Several people suggested I put a Polyphaser on the coax output of the Comtek box. . .the coax going to the rig.  In my case, the lightning did not enter the Comtek box via the coax going to the rig (it's buried with a Polyphaser on the rig end of the coax).  Lightning came into the Comtek box from one of the vertical elements of the array itself.  

Several people suggested spark gap arrestors, shorted 1/4 wave stubs, or choke shunts (ala Array Solutions) on the elements.  These approaches would, no doubt, help.  Unfortunately, I didn't get a firm answer to the real question.  Will the addition of the standard DC blocked Polyphasers (basically, a big series cap) installed on one end of each coax phasing line, alter and destroy the correct phasing of the array?  A couple of people said they thought it would but weren't sure.  It would seem that inserting a large amount of C in series with the phasing line would have to alter its electrical length. . . and ruin the phasing in the process.  If so Polyphasers wouldn't work, leaving the spark gap, stub, or choke solutions.  Is my thinking on track?

73 . . . Dave
W0FLS