Hi Gene,
In the early 1970's, I took a direct lightning hit in the middle of San
Jose in the Santa Clara Valley where lightning is a rare occurrence.
Among the many blow outs were an aluminum ground wire that blew apart, the
front end of my 75A4 and some of the PL259s on my beam. The RG8 coax
completely exited from the connector! The connector was and plug were an
ugly black, there were splatters on the wall and the coax end was black
with the shield wires missing. I'll have to go back and look again but I
think the center conductor did exit the connector.
73,
Joe, W1JR
At 10:31 AM 5/14/2002 -0400, EUGENE SMAR wrote:
>TT:
>
> Speaking of lightning and Polyphasers, I've often wondered about the
>use of PL259's with lightning suppressors/arrestors. I've seen it written
>on this reflector numerous times that one should not rely on a soldered
>connection to a ground rod or other grounding conductor. During a
>high-current strike this connection would melt and the electrical path to
>ground would be destroyed. I agree with this recommendation because it
>makes sense.
>
> Yet on these very same pages many of us expound upon the wisdom of
>using lightning suppressors with (soldered) PL-259 coax connectors. Should
>there not also be a mechanical connection from the coax shield to a nearby
>ground point just ahead of the Polyphaser or other suppressor? (The
>installation at my tower has this configuration by virtue of the shield
>ground at the base of the tower, a foot away from the suppressor on each
>coax run. But it was coincidental that the shield is grounded so close to
>the lightning suppressors at this QTH.)
>
> But what of the soldered center conductor? Wouldn't this connection
>also melt during a high-current strike?
>
> My professional experience with such suppressors has been at commercial
>tower installations where hardline coax and mechanical compression
>connections to the shield and center pin are the norm. But the use of
>soldered connections in amateur lightning supression is troubling - at least
>to me. I hope the QST articles shed some light on this question.
>
>73 de
>Gene Smar AD3F
>
>-----Original Message-----
>From: Pete Smith <n4zr@contesting.com>
>To: towertalk@contesting.com <towertalk@contesting.com>
To: <towertalk@contesting.com>
>Date: Tuesday, May 14, 2002 4:17 AM
>Subject: Re: [Towertalk] Lightning Protection by Ron Block in QST!
>
>
> >At 06:31 PM 5/13/02 -0500, WA9ALS - John wrote:
> >>It's great to see this subject get some attention in QST! -Maybe- it will
> >>help dispell some of the myths about lightning protection.
> >
> >I agree, as long as the Polyphaser guys acknowledge that most ham
> >installations do not need to be connected to their antennas 24/7, and that
> >their solution will not be cost-effective or EFFECTIVE, period, for many of
> >us. Unless you know you have an adequately low-inductance ground
> >connection for your station, all the line protectors in the world will not
> >protect your equipment against a lightning hit. I'd much rather disconnect
> >every conductor outside the house and know I'm safe than gamble on being
> >able to hold my shack at ground potential through "the big one."
> >
> >73, Pete N4ZR
> >
> >_______________________________________________
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> >Towertalk@contesting.com
> >http://lists.contesting.com/mailman/listinfo/towertalk
>
>
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