[maemo-developers] N800 audio connector jack

[From: Erik Hovland]

On Wed, Sep 05, 2007 at 02:24:52AM +0300, Jami Pekkanen wrote:
> Hello,
> 
> This isn't exactly maemo specific question, but I think this is the best 
> forum anyway.
> 
> I'm trying to solder together an adapter that splits the N800's 4-pole 
> audio plug to two separate 3.5 mm females so that I can plug in separate 
> input and output devices, eg electric guitar input and amplifier output 
> (with maemo doing effects in between).
> 
> So I took apart the headset that comes with the device and got the 
> output part working fine, but I don't seem to get any signal to the 
> input. In fact the device even doesn't switch the internal microphone 
> off when I plug the modified system in.
> 
> I'm assuming that there's two grounds (golden wires, another without 
> coating), left output on a red wire, right output on green and input on 
> white. The guesses were right for output, but as I said, the input 
> doesn't get any signal at all.
> 
> Is it possible that something special is required in the input 
> connection? There at least seems to be some resistors in the headset's 
> circuit, but I assumed they are just for the push-button. Also does 
> anybody have a pinout for the jack?

I know of a pinout for a very similar device:
http://web.it.kth.se/~maguire/iPAQ-photos/iPAQ-audio-adapter.html

E

-- 
Erik Hovland
mail: erik at hovland.org
web: http://hovland.org/
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