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From: John Tserkezis on 3 Apr 2010 20:04
bob urz wrote:

> An individual reported getting shocked when he went in his aluminum back
> door. People thought he was nuts. Turned out, when a contractor was
> putting in some siding that had insulation with a aluminum backing on
> it, a nail penetrated both the siding a a live wire that was too close
> to it. This made a path somehow to energize the door.

This is exactly what happened with the Australian home insulation fiasco.

Background is: Government thinks it would be a good idea to subsidise
the installation of home roofing. Allows all and sundry to do the job.
All and sundry suddenly can't cater for the demand, and start hiring
local Joe Idiot as a contractor/worker.

So far this is OK, but installers stopped using normal pink batts, and
started using thinner insulation with aluminium backing (lots cheaper,
so through the subsidy, they make lots more money), laying that over the
roofing structure, and nailing it in place.

Local Joe Idiot who doesn't understand anything about that black magic
called electricity, promptly hammers the nails through live wires, and
kills himself.

That happened four times so far if I recall the reports, along with the
usual spouts of house fires if the installers weren't killed right away.

Even the pink batts were not immune from screwups. Apparently, local
Joe Idiot was placing the fibres directly over downlights. No
ventilation means heat, means fire, means house burning down.


They're still arguing on who to blame. The Government who fostered the
greedy environment, the registered installers who were legally allowed
to hire morons AND for apparently not training them, but have stopped
short of blaming the four who have died, because they didn't know that
putting a nail through a live electrical cable will probably kill you.
Or it's not politically correct or some such rubbish.

All of the above would be my vote.
From: William Sommerwerck on 3 Apr 2010 20:40
>> I've been reading a book on the history of telecommunication.
>> Using the earth as a return path was abandoned in the late
>> 19th century, because it allowed all sorts of electrical garbage
>> to get into the telephone signal.

> HAH, it STILL gets in there.

Yes, but this was "mass quantities" that sometimes obliterated the speech.


From: David Nebenzahl on 3 Apr 2010 22:01
On 4/3/2010 7:06 AM William R. Walsh spake thus:

> While it's an amusing story, I'm pretty sure you'll find that its
> authenticity is dubious and that substantially the same story has been
> passed around in several different settings.
>
> The one I'm familiar with is set in the UK, but all other major
> details remain similar.
>
> Can't find it on snopes but I'm pretty sure it's there *somewhere*.

Killjoy!


--
You were wrong, and I'm man enough to admit it.

- a Usenet "apology"
From: Dave Plowman (News) on 4 Apr 2010 05:42
In article <rbQtn.57169$y13.8084(a)newsfe12.iad>,
Bill Janssen <billj(a)ieee.org> wrote:
> > I did wonder. Ground returns were sometimes used much later to provide a
> > phantom circuit(s) over two ordinary pairs. But poor quality.
> >
> >
> Phantom circuits using two pair of wires did not use ground return. And
> the quality
> of speech was as good as the "side" circuits with maybe reduced loss.
> The "side" circuits
> have to be identical though. If they are not, then from the unbalance,
> you can get noise and power line hum.

A standard phantom circuit does not indeed use a ground return. But some
versions do. Early railway signalling circuits, for example. Or a second
phantom circuit from two pairs.

--
*Cleaned by Stevie Wonder, checked by David Blunkett*

Dave Plowman dave(a)davenoise.co.uk London SW
To e-mail, change noise into sound.
From: Mark Zenier on 4 Apr 2010 13:51
In article <hp7tsl$7pc$1(a)news.eternal-september.org>,
William Sommerwerck <grizzledgeezer(a)comcast.net> wrote:
>It sounds like a backwards construction from "pissing and moaning".
>
>I've been reading a book on the history of telecommunication. Using the
>earth as a return path was abandoned in the late 19th century, because it
>allowed all sorts of electrical garbage to get into the telephone signal.

For some systems, (Bell, I think), party line phones used various
connections so that only the called party heard the ring. It allowed
three households per line. tip-ring, tip-ground, ring-ground.

That's how my parent's house (installed in late '40s) is wired inside.
Tip and ring on a twisted pair and ground, at each 4 pin outlet.
Originally a party line, but they converted everybody to private lines
in the late 1950's.

Mark Zenier mzenier(a)eskimo.com
Googleproofaddress(account:mzenier provider:eskimo domain:com)

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