C860 Microphone Gain Adjust

[Mjolinor]

I just fitted a microphone off an old Nokia phone inside my C860. The gain is a bit low.

Can anyone tell me if there is an ap to adjust it, I'm using Cacko 1.23 lite.

[speculatrix]

I just fitted a microphone off an old Nokia phone inside my C860. The gain is a bit low.

Can anyone tell me if there is an ap to adjust it, I'm using Cacko 1.23 lite.
[div align=\"right\"][a href=\"index.php?act=findpost&pid=108532\"][{POST_SNAPBACK}][/a][/div]

does the Sharp application "sound recorder" not have some sort of gain control?

[speculatrix]

p.s. I would be very interested in knowing how you did this. does the stereo headphone output still work, ie. have you somehow re-routed the audio in?

any chance of some pictures?

[Mjolinor]

It sure do, thank you.

Don't know if it remembers the settings. I'll try it when the champagne has worn off

[Mjolinor]

I'll take some pictures and post them if you like. The stereo headphones still work fine as the microphone is much higher impedance. There is no magic involved in the microphone / speaker switch. If you plug stereo headphones in and shout at the left one while recording then it will record, pretty poorly for sure but it does record.

[Mjolinor]

I took the mic out of a Nokia 6110. It is about 5 mm diameter.

If you take the bottom off the Zaurus you can make a hole large enouigh for the mic to fit in in the top left corner above the battery. The hole does not go through to the outside, only through the inside plastic, it uses the hole on the back of the Zaurus for the sound to enter the mic. I suppose tehis bit of plastic is to lock a docking station or something, I don't know. This allows the mic to sit in the hole when you stick it to the correct place on the motherboard. (see attached pics)

The wiring can be picked up from the headphone socket but it was a long way so I traced it to the end of the red line, that shows the routing of the wire, under the SD slot and picked up an earth connection for the second microphone connection, glued the mic to the motherboard and put it back together.

The pictures are off a spare motherboard. If you need more specific then I'll have to dismantle it though I would prefer not to.

[speculatrix]

ah, I see. so the microphone is always live, just that it has no effect until the kernel switches the audio path to input/microphone. I had been wondering if you separated the audio path, so that the input signal was disconnected from the output, thus allowing you to have stereo audio output AND have sound input too.

hmm. scratches head. is a pity that there's no way to add stereo input to the Z, it'd make a useful recording tool

and I did read somewhere about an oscilloscope program for the Z. I have been wondering about hacking together a simple A-D converter for the Z to achieve this. I did look into two different USB oscilloscope devices but they're well over US$100, and have little or no linux support.