I have 1650 computers (ok slot machines) on my data network, all grounds are
solid copper strap, before I changed to solid copper the previous tech used
braid. Once the braid got wet and corroded with drink spills and other nasty
fluids (don't ask you don't want to know) they were useless. Modern video
slots are a pc and proper grounding in a large building is a must. And we
have some rf links I deal with, all use copper strap. To make it more fun we
have all kinds of uhf radio rf in the building for communications.
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com]On Behalf Of Frank Donovan
Sent: Monday, January 17, 2005 6:40 AM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] There's 'ground', and then there's 'ground'
Keith,
If you work as a professional in the industry, or if
you're interested in spending several hundred dollars,
purchase the EIA/TIA and IEEE grounding and bonding
standards that provide exactly the engineering foundation
information you are seeking. If you want to spend the
money, let it be known on the reflector and I'm sure
you will get the specifics.
Otherwise, I suggest you visit a commercial cell site, a
radio transmitter site, or a large computer facility in your
area.
Let us know how many braid straps you find. If you
find any, let us know how long they are.
73!
Frank
W3LPL
donovanf@erols.com
----- Original Message -----
From: Keith Dutson <kjdutson@earthlink.net>
To: <towertalk@contesting.com>
Sent: Sunday, January 16, 2005 3:59 PM
Subject: RE: [TowerTalk] There's 'ground', and then there's 'ground'
> >Its been well proven that braided strap has far too much inductance to be
> of any utility above 2 MHz.
>
> OK. So where is the proof?
>
> I am thinking any writing you can find is based on the use of braid that
of
> poor manufacture or has corroded, or both. Poor or corroded braid can act
> like many very small wires to create substantial impedance. However, well
> constructed braid acts more like a solid bar of metal, but with the
> flexibility required for many installations.
>
> Keith NM5G
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Frank Donovan
> Sent: Sunday, January 16, 2005 10:35 AM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] There's 'ground', and then there's 'ground'
>
> Here's a clarification, pointed out by an attentive towertalkian:
>
> My previous e-mail was not intended to refer to cables that use a braided
> shield under a jacket. A tight jacket compresses the braid and it's a
very
> effective RF conductor, provided that the braid is not corroded.
>
> Rather, my comment was intended to apply to to the inappropriate use of
> braided strap for RF grounding or lightning protection. Its been well
> proven that braided strap has far too much inductance to be of any utility
> above 2 MHz.
>
> So... Lets try again:
>
> Discard all forms of "braided" strap.
> Braid is something a girl does to her hair.
> Braided strap is a poor RF conductor and it's a terrible conductor of
> lightning energy.
>
> Use braided strap only for DC and audio applications, its just an inductor
> for RF or lightning protection applications.
>
> Here's an excellent reference from the many industry sources on this
topic:
> http://members.cox.net/pc-usa/station/ground5.htm
>
> 73!
> Frank
> W3LPL
> donovanf@erols.com
>
>
>
> _______________________________________________
>
> 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
_______________________________________________
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.
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_______________________________________________
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.
_______________________________________________
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