I was emailing with Rich, KL7RA, about a year ago on this subject.
He shared some jpeg's with me, showing the 1/4in. teflon insulator
sheet he had at his Rohn 25G tower base for 32 years, for a series-
fed vertical on top band. He was moving it from an arctic location
to somewhere nearer to the ocean. There was probably not that much
thunderstorm activity at such a northerly QTH (?) No mention was
made of any parallel lightning arrestors being placed in this
installation. In any case, the photos showed clearly there had been
no mechanical or electrical damage to the teflon sheet over this
extended time frame. BTW he had also wrapped some sort of canvas
cloth over the base area to keep the weather off of it. While it
certainly would not hurt to use those big power line insulators as
W8JI does, it seems to me that, with properly adjusted spark gaps
at the base, insulator plates ought to hold up fine in the event
of lightning strikes, so long as you can live with that large
shunt capacitance. 73, David K3KY
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