Responding to Jim (but not sure which one!) --
You say
"That's why I was thinking that coming up with a suitable peer-reviewed
document aimed directly at hams would be useful. Not an application
note from a mfr or sales oriented source; not that information from
PolyPhaser or ICE isn't useful, but they have an obvious orientation,
so you'd want independent backup."
This rings a bell. We are _amateurs_, and while some of us are
engineers and scientists in real life, very few if any of us are
professionals when it comes to specialized subjects like grounding and
lightning protection.
I observe that a lot of commercial and ham literature (PolyPhaser's
material and most everything on the web) have a lot more philosophy
than science. They say to do this and that but don't give references,
and they're not peer-reviewed. I can't find statistics about how well
their equipment has performed in real installations, certainly not for
hams.
To develop a standard for grounding of amateur radio stations seems to
be beyond what our economically small hobby can support. Industry
practices for cell towers and similar installations may be the best
we'll ever get. Those facilities are quite standardized and are often
built from scratch.
[If you want to convince me that a particular lightning protection
system - grounds, surge suppressors, etc. - is safe and effective, you
have to _test_ it under realistic conditions. We get anecdotes on
TowerTalk, but I don't know of any serious testing.]
The problems of RF grounding and AC safety grounding are a little
easier, because you can easily experiment on the RF side (it only needs
to be good enough), and residential electrical codes help you with the
AC.
Most of us install radios and antennas where we can, and we don't build
bonded metal buildings with controlled cable interfaces and all that.
What I want to know is how I can make the best installation in my
particular residence with my particular array of trees, utility lines,
etc. without spending too much money. It's never going to be easy to
use a standard developed for an industrial situation.
So I end up with an _amateur_ installation, hopefully using enough of
standard practices that my station and I will survive the most likely
environmental threats. And with some luck, I will even be able to work
some DX.
73, Martin AA6E
> Date: Sun, 6 Feb 2005 20:07:21 -0800
> From: "Jim Lux" <jimlux@earthlink.net>
> Subject: Re: [TowerTalk] Comprehensive Grounding Tutorial on Web
> To: <towertalk@contesting.com>, "Jim W7RY" <w7ry@centurytel.net>
> Message-ID: <003b01c50cca$867886a0$32a8a8c0@LAPTOP152422>
> Content-Type: text/plain; charset="iso-8859-1"
>
>
> ----- Original Message -----
> From: "Jim W7RY" <w7ry@centurytel.net>
> To: <towertalk@contesting.com>
> Sent: Sunday, February 06, 2005 7:14 PM
> Subject: Re: [TowerTalk] Comprehensive Grounding Tutorial on Web
>
>
> > This is hardly comprehensive.
> >
> >
> > Lot's of details left. Other have also pointed this out.
> >
> > I would recommend a TIA/EIA document or similar.
> >
> >
> I suppose the problems with TIA/EIA or IEEE documents are the
> following:
>
> 1) Too much detail (nobody really wants to read a 200+ page
> document)
> 2) Not specific to ham applications (we're not grounding substations,
> nor
> cell towers, etc.)
> 3) They aren't available online for free (hams are cheap, and aren't
> about
> to pay $50 for the IEEE spec)
>
>
> That's why I was thinking that coming up with a suitable
> peer-reviewed
> document aimed directly at hams would be useful. Not an application
> note
> from a mfr or sales oriented source; not that information from
> PolyPhaser or
> ICE isn't useful, but they have an obvious orientation, so you'd want
> independent backup. (No "NASA bought Static-Cats, so they must work"
> nonsense) With a suitable bibliography and references to look up
> more info,
> etc.
>
> Preparing such a thing would be a lot of work...
>
> >
> > 73
> > Jim W7RY
> >
>
>
_______________________________________________
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