A number of us have purchased an iTrip compatible with one of the first iPods. Most of the time, it outlives the iPod. Cobus decided to recycle one of them and use it with his laptop.
I opened my iTrip, then checked out the wiring diagram at http://www.maushammer.com/systems/ipod-remote/ipod-remote.html
I then installed the board in a plastic housing with a spot for batteries (in this case a TV remote), to which I attached a 3.5" audio jack (taken from some headphones)
The power resistance then needs to be removed (the cylinder with the coloured rings - maroon, black, maroon, gold) as the iPod provides 3.5 volts whereas our two batteries (rechargeables, of course!) only total to 2.4 to 2.7 volts. No more need to lower the power level at the entrance to the iTrip!
Think about drilling a small hole in the casing to be able to see the diode light up when the iTrip is broadcasting.
For the record, welds were made by heating a nail on a gas stove, seeing as how I did not have a soldering iron during the holidays. :-)
Going a little further with this modification, it would be fairly simple to instead put a slightly larger resistance on, rather than completely removing it, and powering the device directly using the 5 volts from the USB bus.
