Crystal radio is simplest but not simle in practical terms when hooking good aerial and earth. Better go for regenerative receivers. In what frequency you are interested.
ZN414 in TO92 package. The ZN414 was a low cost, single-chip AM radio integrated circuit
FM Receiver with one Transistor and Audio Amplifier seems like an interesting project
**broken link removed**
but the pcb layout is not given
Can anyone please provide the pcb layout?