At 03:00 PM 12/4/2005, you wrote:
> am wanting to build a patch cord from an old headphone cable. The
>cable looks like copper but I can not get any length of it to show
>continuity with a good meter. It must conduct or it would not have
>worked for the headphone, any idea about what I am working with?
>
>Gerald White Muscatine,IA
Hi Jerry:
My bet is that it is a tiny copper foil, spiral-wrapped around vyer tiny
cotton threads, and then many laid side-by-side to make a very flexible
phone cable. Use a hand-lens or very close-up glasses to check.
I successfully fixed several in my youth. The cotton provides ALL the
strength, and the thin copper provides, as you guessed, the conductivity.
The way I repaired them was this:
Separate several inches of the cord into line one and line two.
Unwrap each line into two parts, and wrap them together:
1 a cotton cord which you tie tightly to a connector
(like a phone plug body solder lug) and
2 all the tiny copper foils get wrapped together for several inches,
then tin and solder the first 1/2 inch and connect it to your
new plug's electric terminals.
I am probably not describing this at all well, but just please understand
that, when done, the cotton and knots will provide all the mechanical
support should the cord get yanked, and the tiny foil twisting provides all=
the electrical connection. The key concept here is you cannot let the
cotton get hot with the soldering iron because it gets weak, to put it
mildly (it burns). And the copper won't solder well with a lot of burned
cotton in its middle; thus you separate them first into cotton and copper
re-twists.
good luck! and best regards, Marty Michener
MIST Software Assoc. Inc., P. O. Box 269, Hollis, NH 03049
http://www.enjoybirds.com/
Don't blame me, I vote in New Hampshire!
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