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[email protected] Searcher7@mail.con2.com is offline
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Default Fixing Headphones

On Thursday, May 2, 2013 1:12:29 PM UTC-4, Mark Zenier wrote:
In article ,

wrote:

I have a couple of headphones that have stopped producing sound on one


side and I wanted to try fixing them.




I know it will involve locating where the break is, as well as soldering


but I was looking for pointers because I've never done this before.




I assume that the problem is either at the location where the plug


inserts or more likely where the leads enter near the ear pieces.




Any advice from anyone who has done this would be appreciated.






A bit more info might help. What sort of price range?

What type? (cover the ear? headband? earbuds?)

(Apple?, or generic).





The stuff I mess around with are the $10 generic headband type, used with

cassette players, radios, etc.



With those, the sound element generally snap into the headband

and if you unsnap each on, there's two solder points.



Color Code for the typical 3 conductor 3.5 mm/1/8 inch plug



green - left side audio - the tip of the plug

red - right side audio - the ring on the plug

copper - ground - the sleeve (two wires, one each side)



The wires are small (40 gauge?) multi-stranded wire insulated with

thermally strippable enamel. In a two by two zipcord jacket.



(Older cords use miniature shielded conductors with red (right) and

white (left) center insulation and no other insulation on the central

conductor and shield wires. This kind of wire can short out.)





The first step it to unsnap the sound elements from the head band.

(I'm not into earbuds, I suppose there's some way to uncap the

end with the wires). Then you can measure between the solder points

on the element and the plug to find the open conductor(s). See

the color code...



One test is just to tug on the open wire and see if it pulls out.

The most frequent breakage is at the place where the wire exits the

headband, about 3/8 inch down. At this point, cut, strip back about 3/4

inch from the break, tin the wire, remove the old wire bit on the sound

element connection, and re-solder. (If symmetry in the cord matters,

you may have shorten the cord and reinstall on the other side too,

or just put a knot in the other side).



The wire isn't that hard to deal with. You need a high temperature

solder iron to strip off the insulation. (Avoid the smoke!). Just

get a blob on the tip of the iron and use that to strip the insulation

and tin a 1/8 inch or less of the conductor.



A lower temperature iron is suggested to solder to the connection points

on the sound element. There are usually two pads for each connection,

one for the headset cord, another to connect to the speaker coil with

VERY SMALL wire, avoid disturbing that one.



Another breakage point is at the strain relief at the plug end.

Often you can fell the break where the wire has a "soft spot" at the

high stress point.



As most plugs are molded on, it's time for a $.69-$2 for a new plug.

Or a whole cord assembly. (I've seen them in Mouser's catalog, anybody

tried them?)



When putting on a replacement plug, remember to put the outer insulator

on the wire before you solder on the plug assembly.

(See color code..., use your ohm meter frequently).



I often reinforce the strain relief on the wire exiting the plug with

some small (1/16"?) shrink tubing. Likewise the area where the wires

exit the headband. The kitchen toaster works good for shrink tubing. ;-)





Mark Zenier

Googleproofaddress(account:mzenier provider:eskimo domain:com)


I'd need visual aids to understand what is being referred to. But the information on the heahdphones is as follows: “SONY Synamic Stereo Headphones MDR-7502 Professional”. Here’s one on Ebay:
http://www.ebay.com/itm/400426911595

It is the right side that doesn't work. And the plug has two green rings.

I'm wondering if there are replacement ear pads available for this. IF not it wouldn't be worth fixing.

I attempted to check continuity by sticking a sewing needle into both parallel wire leads in order to determine if the break was at the plug and had no luck at all. So it looks as though I'll just have to shotgun by stripping the wires.

From what is said here I should start with replacing the plug. But I haven't been able to find anything via Google as far as an illustrated diagram on how everything is connected.

Do I start by cutting off the plug so that there are on the two leads left? (Of course I'd have to find a replacement first).

I'm not sure how to deal with the leads where they enter the earpieces or if it is possible to open the ear pieces up.

Thanks.

Darren Harris
Staten Island, New York.