Please tell me where Polyphaser it shows that:
"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 ".
I'm intimately familiar with the Motorola R-56 Standards for
Communications Sites, and it contains no discussion about using a lightning
suppressor at both ends of the horizontal run between the base of the tower
and the building.
Polyphaser does not make a readily available weatherproof lightning
suppressor.
Now grounding the shield of the coax is recommended/required every 50-75
feet. Both vertically and horizontally.
73
Jim W7RY
Motorola Senior System Technologist
Polyphaser 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
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|