BNC Coaxial Connectors, the name being an initialism of Bayonet Neill-Concelman, is a commonly used coaxial connector for a wide variety of 50 Ohm and 75 Ohm applications. Originally designed in the 1940s for military applications, both BNC Female Connectors and BNC Male Connectors are now used in radio and video systems and have grown in variety and use case over the decades.
What Is A BNC Coaxial Connector?
BNC coaxial connectors are bayonet style-quick connect/disconnect coaxial connectors that only require a quarter-turn to connect/disconnect. BNC connectors can attach to several types of coaxial or even triaxial cable, such as RG coaxial cable. The BNC connector includes two bayonet lugs on the female connector and the outer connector is equipped with slots that enable easy alignment and a locking feature to ensure positive contact.
What Are BNC Connectors Used For?
Due to this ease of use and ability to carry RF signals to 2 GHz, 4 GHz (typical for RF), 6 GHz, or even 12 GHz to ~500 volts root-mean-square (RMS) maximum continuous voltage, this connector style is extremely popular in 75 Ohm video applications and in an even greater variety of 50 Ohm test and measurement, radio equipment, sensors, instrumentation, and other critical and non-critical applications. The BNC connector is one of the most widely used coaxial connectors as it transcends RF applications and is used in virtually every environment from home audio/video (A/V) equipment, medical equipment, military/aerospace, to nuclear instrumentation. This includes 12G SDI compatibility for 4K and Ultra-HD video use.
BNC Connector Variations
BNC coaxial connectors are made for both 75 Ohm and 50 Ohm characteristic impedance systems, which are generally designed to mate non-destructively. However, mating between 75 Ohm and 50 Ohm BNC connectors is only advisable in applications below 10 MHz where the impedance mismatch has minimal impact on connector interface performance. There are also variations for higher impedances, such as 93 Ohm for ARCNET. There are reverse polarity (RP) BNCs, which reverse the male/female polarity of the connector. These are only generally used to prevent connection of standard BNCs to special RP ports, or for an uncommon high-voltage BNC variant. There are also mini-BNC, a variant that is designed to have a lower profile than standard BNC while meeting all the same specifications. Hence, there are Mini BNC Adapters to adapt from Mini to standard BNC connector styles.