The Benefits of Using a 4 Channel Passive Video Balun

Today, many security equipment and surveillance cameras still use coaxial cables, specifically RG-59, which is a shielded cable that has an impedance of 75 ohms. By impedance, we are talking about the measure of the opposition from an electrical circuit to the passage of the current as voltage is applied through it. Shielded cables are wrapped, most commonly in aluminum, mesh wires, and plastic, preventing external noise from reaching the cable. Additionally, with shielded cables, the desired radio frequency is kept inside the cable. With an impedance of 75 ohms, ideal quality videos will only result if the objects that transmit the signal also have the same impedance of 75 ohms.

Cat5 cables, on the other hand, are more recent technological innovations, which have twisted pairs of wires. The twisting of the pairs actually allows electromagnetic interference from external sources to be canceled out. The problem with Cat5 cables though, is that it is unshielded, which means that there is no shield to prevent outside noise which comes in the form of electromagnetic radiation. This is another reason why Cat5 cables have a different name – UTP cables which stand for Unshielded Twisted Pair cable. Cat5 cables also differ from coaxial cables in one thing: it has an impedance of 100 ohms. 

The camera that has an impedance of 75 ohms and the DVR that intends to receive it at 75 ohms means that Cat5 cables are a mismatch with both the camera and the DVR, along with everything else. How do we solve this problem?

A 4 channel passive video balun is the best way to prevent loss of information that is brought about by lengthy, unshielded, or mismatched cables. With a 4 channel passive video balun, the mismatch of ohms going to and from the cable will be corrected. Additionally, external noise cancellation is also prevented as well as other video signal attributes such as white balance. A 4 channel passive video balun is specifically designed to solve these problems and fortunately for us, they come at a cheap price.

Video baluns are used in CCTV systems and some of the pieces we are familiar with include active video baluns, HDTV baluns, keystone video baluns, and rackmount video baluns.