Record players and Hand held radios

@Iwillwait No power switch since no power required. Some had an alligator clip to clip to a length of wire or any floating metal as an antenna ie a window frame or gutter. Mine had a loop antenna built in. A crystal radio is always on basically.

@Gibbon explain that, no power needed, how is this getting power?

@Iwillwait An inductor and capacitor circuit connected with a diode, the crystal, are directly resonated by the AM signal when tuned. This is very low power fed into a high impedance speaker in the earphone. This allows hearing the audio without external power. This existed decades before the 9 volt battery.