Has anyone tried to convert the old Nokia mini-car kit PPH-1 (with a 2.5mm 4-pole jack (http://pinouts.ru/CellularPhones-Nokia/nokia_headset_pinout.shtml)):
(http://pinouts.ru/images/nokia_3210_handsfree.gif)
to pop-port (http://pinouts.ru/CellularPhones-Nokia/nokia_pop_pinout.shtml)?
BTW there is no buttons, or built in microphone in the PPH-1...
The charger pins are 1 and 2 from the pop-port are easy to find in the PPH-1. The rest is bit more tricky. There are five wires other than the red-black 6v Vin and GND (why 5 - it is a 4-pole connector! - oh, I got it there is a yellow cable going straight from the ext mike socket in the PPH-1 to the GND in the charger plug going into the phone)
Should ACI be connected somewhere?
Should I short pins 12 and 14 (and 11 13) to convert to mono?
Where should the shield GND be connected?
Is there anything else I should worry about?
Mateusz[/url]