Eugene
My antennas were hit by lightning late last year .A PL259 was welded
(Melted) to a female Bulkhead connector where I should have disconnected My
Antenna.......I had left One connected......When I went to disconnect it
(Not knowing at that stage that the antennas were hit) I had to get
Multigrips to undo it.....found the outer piece of the PL259 was melted to
the female bulkhead thread ----- then found - where the two outers touch
together - they were also melted ---- but NOT together -- the white
insulator that holds the center pin in place in the PL259 & female bulkhead
connector were both black with carbon where the lightning arced to the
center Pin...... I am taking My antennas down next week. I have new
replacements awaiting erection to the top of the tower...... The lightning
also struck the galvanised steel roof about 3 inches above the coaxial
cables on their way into the house. The lightning went into the shack and
left burn marks on the back of My antenna switch where it connected to an
earth braid.......I have a ground rod under My desk in the shack.....and the
tower was earthed --- but the heavy cable to the tower had a 90 degree bend
in it.....should have been less than 30 degrees....I have been busy reading
up on Lightning protection......
It also took out My computer and rotator.......but the printers & scanner
were untouched.... .....My transceivers were disconnected at the
time......and the center pin in the PL 259 is still soldered in.....(I do
use a lot of solder on PL259s)
I am thinking of running all My cables from the tower to the house in a
steel pipe......I used PVC piping before.
I am also going to Ground (earth) My coaxes at both ends of the
tower......and all the ground rods have to be connected together......and
then connected to the Mains (240v AC) ground stake......from What I have
read and what has been sent to Me via emails......You can bleed the
lightning charges to ground BEFORE they add up to very large voltages &
currents, by having Your tower well grounded with ground rods.......
Ok......I hope all this makes sense Eugene..as its 1.37am local here and I'm
NOT even going to read what I've written....
Best Wishes from down under...
Lee Noonan VK2LEE
http://www.qrz.com/vk2lee/
http://www.qsl.net/vk2lee/
----- Original Message -----
From: "EUGENE SMAR" <SPELUNK.SUENO@prodigy.net>
To: <towertalk@contesting.com>; "Pete Smith" <n4zr@contesting.com>
Sent: Wednesday, May 15, 2002 12:31 AM
Subject: Re: [Towertalk] Lightning Protection by Ron Block in QST!
> 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
> >
> >_______________________________________________
> >Towertalk mailing list
> >Towertalk@contesting.com
> >http://lists.contesting.com/mailman/listinfo/towertalk
>
>
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