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Richard Crowley Richard Crowley is offline
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Default USB Headphones hack - Soldering a 3.5mm plug instead of the headphones

wrote ...
I have a cell phone with a mini-usb plug on it.. the camera also came
with a set of earphones that plug into this usb connector, however, I
would like to go from this mini-usb to a 3.5 mm plug instead of the
headphones (my car has an aux plug input). The earphone/usb cable has
a little 3/4" case that has a microphone and Im guessing a amplifier.


So..

I opened the the little case, and sure enough where there are 3 wires
"L", "R", and ground that are going to the earbuds. The ground and
"R" wires were both going to the right earbud. So I desoldered these 3
wires from the board, and soldered the 2 wires coming from the 3.5 mm
plug.

The problem is, Im getting tons of noise, and at VERY low volume. Im
guessing this is because the ground on the plug isnt connected to the
ground of the amplifier/microphone board. However, the 3.5 mm plug
doesnt have a 3rd (ground) conductor to connect.. it only has a white
and red wire, nothing else.

If my post above, wasnt confusing enough, here's a totally blurry
picture that I took with the cell. Its hard to see anything on it,
but the red and white wires on the right are going to the plug.

http://i6.tinypic.com/5xe5fth.jpg

Im probably missing something obvious, but what am I doing wrong? How
can I connect a plug to where the headphones used to go?


What cell phone?
What camera?
What does the camera have to do with anything?
Are you trying to connect the output of your cell phone
to the aux input of your car radio?
Did you try your two wires connected the other way
around?
Is your 3.5mm connector stereo (tip-ring-sleve)?
If so, why does it have only 2 wires?
Is the wire to your 3.5mm connector shielded?

I would have left the earbud wire as it was and
chopped it in half to install the 3.5mm connector.
That way you know what is what out of your little
case. And you can install a plug on the remaining
earbud wire to be able to use your lash-up either
way.