This isn't the simplest radio (or oscillator) you can build. To get the nearest AM-station, simply put a resistor, an a diode together and attach 20 m of wire and an earphone on its side. Voila!
When I was a kid in the 80's, my parents once grounded me from my computers and radio. I wired a diode and earphone to the TV antenna lead in my room, and could listen to the town's radio station again. No resistor and completely the wrong sort of antenna, but I guess radio can be very forgiving when there's a single strong nearby signal. Good times. :)
I remember a TV program, in Spain in the 70's. They explained how to do one AM radio with one transistor, an AA battery, half a metre of copper wire and an earphone. Worked fine.
