What Is a BNC Cable?
A BNC cable is a type of coaxial cable commonly used in high-frequency analog signal measuring devices, such as oscilloscopes.
BNC cables come in two impedance varieties: 50Ω, typically used for power transmission in radios, and 75Ω, used for transmitting video and audio signals in devices like TV receivers. The cable consists of a coaxial cable fitted with a BNC connector, known for its quick connect-and-disconnect capability and locking mechanism that secures the connection without the need for screwing.
The term, BNC, is believed to be derived from Bayonet Neill Concelman, combining the bayonet locking mechanism with the name of the connector’s inventor, Neill Concelman. Other theories suggest it stands for Bayonet Connector or British National Connector.
Uses of BNC Cable
BNC cables are used in various fields, including telecommunications, measurement, computing, and audiovisual equipment. In telecommunications, they are used for high-frequency signal transmission in equipment like FA controllers. In the audiovisual domain, 50Ω cables serve as LAN cables, while 75Ω cables are used for video and audio connections.
Due to their compact size, affordability, and excellent frequency characteristics, BNC cables are also used as an alternative to RCA connectors for transmitting electrical signals.
Principles of BNC Cable
BNC cables feature a bayonet lock mechanism for easy engagement. This mechanism allows for a secure connection with a simple twist and is designed to prevent accidental detachment even when the cable is pulled, due to its spring-based locking system.
Structure of BNC Cable
The cable combines a BNC connector with a coaxial cable and may include branched lead wires at the tip. Various types are available, including those with male connectors on both ends, branching with a clip for measurements, and robustly soldered lead wires.
These cables often use UL1015-AWG18 wires, and lead-free solder is utilized for connections, making them environmentally friendly. Before shipment, BNC cables undergo several quality assurance tests, including insulation and withstand voltage tests.
How to Choose a BNC Cable
When selecting a BNC cable, consider the application: 50Ω cables for oscilloscopes and precision measurements, and 75Ω cables for video and audio transmission, such as in household TV setups. For applications requiring high power transmission or precision measurement, specialized commercial coaxial cables are recommended.
BNC cables are also used for audio equipment connections, analog surveillance camera transmissions, and in industrial applications with surge protectors and arresters.