The rate at which an electrical current alternates, usually measured in Hertz (Hz). Also the way to note a general location on the radio frequency spectrum such as 800 MHz, 900 MHz or 1900 MHz.
850/1900 & E900/1800 MHz
Audio
FM-radio
Tono polifónico
Polyphonic ringing tones are played through a speaker rather than an ordinary buzzer, which means that you get vastly improved sound quality for melodious ringing tones, message alerts, and gaming sounds.