BTW, the Polyphaser is to protect the equipment, not the coax. Grounding of
the shield at the 50-75 foot interval is what protects the coax (and the
equipment). The theory is to drain the charge off of the coax shield as
much as possible.
73
Jim W7RY
At 08:50 AM 4/2/2005, you wrote:
>Not necessarily. According to the ARRL Handbook (or maybe it's the Antenna
>Book) and Polyphaser, the optimum configuration is to install lightning
>suppressors at *both* ends -- at the tower and at the entry to the house. I
>believe the main idea is to protect the coax run between the house and
>tower, which is an important consideration if it's expensive hardline and/or
>buried in such a way that it would be hard to replace. I would think it's
>also good to have two sets of shunts to ground in case the suppressors at
>the tower get overloaded or fail. The shields should be grounded at both
>ends as well -- at the tower end to a system of ground rods and radials
>connected to the tower and at the house end to the single-point ground.
>
>73, Dick WC1M
>
> > -----Original Message-----
> > From: Gary Schafer [mailto:garyschafer@comcast.net]
> > Sent: Thursday, March 31, 2005 10:14 PM
> > To: Craig Sande
> > Cc: towertalk@contesting.com; Craig Lekutis; 'Gene Smar'
> > Subject: Re: [TowerTalk] Wet setting conduit?
> >
> >
> > Your lightning protection devices should go at the house not at the
> > tower. Ground the shields at the base of the tower though.
> >
> > 73
> > Gary K4FMX
> >
> >
> > Craig Sande wrote:
> > > I finally decided not to risk any compromise to the base by
> > > introducing
> > > a total of 5 conduits. The pour will proceed tomorrow
> > morning per the
> > > original engineering. When the dust settles, I will take my time
> > > installing the conduit runs to the edge of the pier. I'll
> > probably use
> > > a NEMA box mounted nearby for the lightning arrestor
> > devices and have
> > > the conduit enter directly from below. I'll run a 6"
> > copper strap from
> > > the NEMA box to the tower. I'll be sure to snap plenty of
> > pictures and
> > > share my experience when complete.
> > >
> > > Regards,
> > >
> > > Craig, AE7I
> > >
> > >
> > > Craig Lekutis <craiglekutis@wirelessestimator.com> wrote:
> > >
> > > Craig,
> > >
> > > If it's a slab foundation and the PVC entries are not near the
> > > anchor bolts then it might not be a problem since the
> > foundation is
> > > probably designed for its compressive load and its overturning
> > > moment. However, if it's a pier type design, it may be a problem
> > > since it could affect interaction with the shaft and
> > anchor bolts.
> > > Best practice is to do what you are going to do, check with your
> > > engineer. You'll find addition information about
> > foundation design
> > > at http://www.wirelessestimator.com
> > > <http://www.wirelessestimator.com/> .
> > >
> > > Best regards,
> > >
> > > Craig
> > >
> > >
> > >
> >
> >
> >
> >
> >
>
>_______________________________________________
>
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
>any questions and ask for Sherman, W2FLA.
>
>_______________________________________________
>TowerTalk mailing list
>TowerTalk@contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
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