Hi. I'm trying to build myself an in-car radio transmitter, which I will
plug the headphone feed of my Mini-Disc player into, so that I can tune
the car radio in and listen to it.

I've tried a few circuits but so far no luck. I'm testing building on a
breadboard and in the home.

Does anyone know of any successful circuits of this nature, and have any
pointers to them?

Thanks.