A Video Balun enables the transmission of video using unshielded twisted pair wire like cat5 or cat6 instead of coaxial cable. Installers use cat5 or cat6 instead of RG59 cale because it is to run and is lighter. The function of a balun is to transform an unbalanced signal into a balanced signal. When video signal is transmitted over coaxial cable, the distance traveled by the video signal is limited because the signal is in the form of an unbalanced signal that is susceptible to Radio Frequency Interference or noise. Coax cable incorporates special shielding to minimize noise.
Video Baluns transform the video signal into a balanced form in which each wire in the twisted pair transmits an identical signal with opposite polarized magnetic fields. Noise affects each signal equally. When the signals are combined, the noise is cancelled out. By using a designed balun, an unshielded twisted pair wire can transmit video for much longer distances than coax cable and with a lower cable cost.