What is the standard impedance for analog CCTV systems?

What is the standard impedance for analog CCTV systems?

• A. 50 ohms
• B. 75 ohms
• C. 100 ohms
• D. 150 ohms

Answer: (B)

The standard impedance for analog CCTV systems is 75 ohms. This specification is critical because it ensures optimal signal transmission and reduces the risk of reflections that can degrade video quality. In analog video applications, particularly those using coaxial cable, 75 ohms is used because it matches the impedance of the common video signals, which helps prevent signal loss and ensures a clear image. Utilizing coaxial cables with 75-ohm impedance minimizes issues like ghosting, loss of brightness, and other artifacts that can occur with poor matching of cable impedance to source or load. This is why the industry standard for components such as video cameras, monitors, and transmission cables in analog CCTV systems is set at 75 ohms, facilitating better compatibility and performance in video surveillance setups.

The standard impedance for analog CCTV systems is 75 ohms. This specification is critical because it ensures optimal signal transmission and reduces the risk of reflections that can degrade video quality. In analog video applications, particularly those using coaxial cable, 75 ohms is used because it matches the impedance of the common video signals, which helps prevent signal loss and ensures a clear image.

Utilizing coaxial cables with 75-ohm impedance minimizes issues like ghosting, loss of brightness, and other artifacts that can occur with poor matching of cable impedance to source or load. This is why the industry standard for components such as video cameras, monitors, and transmission cables in analog CCTV systems is set at 75 ohms, facilitating better compatibility and performance in video surveillance setups.