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Wire and Insulation Q

I have a few thousand feet of some old plastic insulated twisted pair telephone wire stuck away in my garage that has me puzzled. It's 24 AWG (.5 mm) but the insulation is thicker than usual. The usual overal diameter is .044" or 1.1mm, but this wire is about .065" or 1.6 mm. I've cut chunks off to use in some places, and wherever I cut and strip it, the copper is tarnished like it was stripped and exposed to the elements for years. But that's underneath the insulation. So I'm puzzled as to why the insulation didn't protect it from being oxidized and corroded. Maybe something in the insulation itself?

The color codes don't conform to the ones in use today, probably because things were different a few decades ago. I think that it might be good for hooking up field phones in a forest somewhere. Any ideas?

BTW, I was web surfing and found some interesting info the other day on "Murphy phones" for cave rescue. Might be of some use, somedsy.

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Watson A.Name - "Watt Sun
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Sounds like Quad cable that used to be used for telephone. 4 conductor, not even twisted pairs. They used to use all 4 conductors -- green/red for talk and black/yellow for the ringer, which used to be a bell that drew a fair amount of current at 90VAC.

CIAO!

Ed Nielsen Society of Cable Telecommunicati> I have a few thousand feet of some old plastic insulated twisted pair

Reply to
Ed Nielsen

Bell and voice were driven from the same loop (green/red). The usual install was to use the black/yellow for a second line or for the "Princess" lighted phones. Those phones had small lamps in them. In that case they used a "wall wart" type transformer to power the second pair which was used to power the lamps.

Reply to
George

It seems that some wires, in particular silver plated wire, will tarnish from the plasticizer in the insulation.

Cheers!

Chip Shults My robotics, space and CGI web page -

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Reply to
Sir Charles W. Shults III

I remember tearing into some phones that had them going to the bell, but then again, my memory may be a bit foggy on that. Wasn't quite yesterday.

CIAO!

Ed Nielsen CENCOM

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George wrote:

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Ed Nielsen

Reply to
Stepan Novotill

Some of the old party line phones used a 3rd wire, to determine which of 2 subscribers the call was for.

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James Knott

Were you on a party line?

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James Knott

In article , snipped-for-privacy@comcast.net mentioned...

No, it's a single twisted pair, with odd colors like blue and black. Thanks.

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###Got a Question about ELECTRONICS?   Check HERE First:###
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My email address is whitelisted.  *All* email sent to it 
goes directly to the trash unless you add NOSPAM in the 
Subject: line with other stuff.  alondra101  hotmail.com
Don't be ripped off by the big book dealers.  Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com  You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
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