In this case they are just fancy drip loops. Note the original description,
loops of coax just before connection to a remote relay box. Hopefully the
coax shield is connected to the case ground which is grounded to the tower
or something else where it is mounted... at that point any current on the
outside of the shield (the center conductor is unaffected by the coax loop)
should drain to ground anyway. In my opinion adding a loop at that point
may add a little bit of inductance, but its effect would be to PREVENT some
of the lightning from going to ground through the box ground.... if indeed
it did have enough inductance to do something it would result in raising the
voltage on the shield which would then have a bigger chance of puncturing
the jacket as it tried to go to ground around the loop, most likely to the
case of the switch the hard way!
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> -----Original Message-----
> From: Wes Attaway (N5WA) [mailto:wesattaway@bellsouth.net]
> Sent: Thursday, May 27, 2010 13:58
> To: n4zr@contesting.com; TowerTalk@contesting.com
> Subject: Re: [TowerTalk] Lightning suppression through coax loops
>
> I believe I remember that the old Polyphaser manual had some info about
> coax
> loops and bends. The idea is simple, and makes sense, because the
> grounding
> at the tower and at the entrance to your house, etc., is creating a
> voltage/current divider that will, ideally, shunt most of the energy to
> ground before it gets to your house.
>
> The Polyphaser manual explained that loops and bends in coax runs toward
> the
> point of entrance add inductance to that path and cause it to be
> incrementally less attractive for the lightning energy.
>
> I see no reason to doubt this because it is simply a practical application
> of Ohm's Law.
>
>
> ------------------ Wes Attaway (N5WA) ------------------
> 1138 Waters Edge Circle - Shreveport, LA 71106
> 318-797-4972 (office) - 318-393-3289 (cell)
> Computer Consulting and Forensics
> -------------- EnCase Certified Examiner ---------------
>
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Pete Smith
> Sent: Thursday, May 27, 2010 7:10 AM
> To: TowerTalk@contesting.com
> Subject: [TowerTalk] Lightning suppression through coax loops
>
>
>
> 73, Pete N4ZR
>
> The World Contest Station Database, updated daily at
> www.conteststations.com
> The Reverse Beacon Network at http://reversebeacon.net, blog at
> reversebeacon.blogspot.com
> I bought an Ameritron RCS-10 antenna switch at Dayton, and in reading
> the manual (please, no giggling) I note that it calls for a two-turn
> loop in each antenna coax line just before entering the relay box.
> These are described as "drip and lightning retarding loops." The manual
> is quite prescriptive (for example, "keep coils spaced from each other
> by vertical or horizontal separation of 2" minimum"), and I get the
> "drip" part, but I wonder what the real, practical effect of these loops
> would be. Is there enough inductance to offer any practical blocking
> effect for induced voltages resulting from a nearby strike?
> _______________________________________________
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