electrical switching from cellphone to ipod?


2010-10-04 5:47 pm
I am trying to create a cable that I can plug in any type of headphones and any type of microphone with external PushToTalk button for cellphoneuse. into a box with one input from my ipod and one from my cellphone. both use 3.5mm TRRS jack.

what I would like to do is basicly listen to my music but when I get a phone call or updates from my phone gps, it drops(cuts) the music from my ipod and only gives me the phone. this basically for my motorcycle helmet.

I know that when I get a call the headphones go live with sound so there is a voltage but I have no clue how to get that to power something like a relay to break the ipod connection and make the phone connection.

any ideas at all would be helpful. I know I can do this with blue tooth but I actually don't mind the wires if I can get it right.