Before revision: DirYesDir YesDir:// *(save)=(5.09003*mV*) Yes Applicability to early radio and television In the early days of radio, mains electricity was supplied at different voltages in different places, and either direct current (DC) or alternating current (AC) was supplied.
After revision:  Applicability to early radio and television In the early days of radio, mains electricity was supplied at different voltages in different places, and either direct current (DC) or alternating current (AC) was supplied.