Ultra-Budget Portable Bluetooth Speaker

Wireless speakers are composed of two units: a main speaker unit combining the loudspeaker itself with an RF receiver, and an RF transmitter unit. The transmitter connects to the audio output of any audio devices such as hi-fi equipment, televisions, computers, mp3 players, etc. An RCA plug is normally used to achieve this.  Batteries may last for 3 to as long as 24 hours; almost all wireless speakers operate on rechargeable batteries that are not replaceable, so that the lifespan of these speakers is that of their batteries. The signal frequency range used by wireless speakers is generally the same as that used by cordless telephones — 900 MHz. Many wireless speakers feature variable transmission channels that can be set using a tuning knob to overcome potential RF interference with other nearby wireless devices, such as cordless phones or baby monitors.