amplifier electronic equipment that increases strength of signals passing through it
clock radio a radio that includes a clock that can be set to turn it on automatically
crystal set an early radio receiver using a crystal detector
detector any device that receives a signal or stimulus (as heat or pressure or light or motion etc.) and responds to it in a distinctive manner
demodulator,
detector any device that receives a signal or stimulus (as heat or pressure or light or motion etc.) and responds to it in a distinctive manner