Connectors - TNC

TNC Connectors

TNC (Threaded Neill-Concelman) connectors are 50-ohm coaxial RF connectors closely related to the BNC connector. The TNC replaces the BNC's bayonet coupling with a threaded 7/16"-28 coupling, providing a more secure connection and generally better RF performance at higher frequencies.

The connector is named for Paul Neill and Carl Concelman, whose work is also reflected in the name of the BNC connector. TNC connectors are widely used in RF communications, antennas, test equipment, commercial radio systems, wireless equipment, and applications where a threaded connection is preferred because of frequency, vibration, or environmental considerations.

50 Ohm and 75 Ohm TNC Connectors

The standard TNC connector is commonly encountered as a 50-ohm RF connector. 75-ohm TNC versions also exist for applications requiring a 75-ohm impedance. When selecting a connector or adapter, the impedance and physical interface should be verified for the intended equipment and system.

Standard and Reverse Polarity TNC (RP-TNC)

TNC connectors are available in both standard-polarity and reverse-polarity configurations. Reverse-polarity TNC, commonly called RP-TNC, changes the gender of the center contact while retaining the basic mating interface. RP-TNC connectors are frequently encountered on wireless and antenna equipment.

Because standard TNC and RP-TNC connectors can look very similar externally, identify both the connector body and the center contact before ordering a replacement connector or adapter.

TNC vs. BNC

TNC and BNC connectors are closely related, but they use different coupling systems. BNC uses a quick-connect bayonet coupling, while TNC uses a threaded coupling. The threaded TNC interface provides a more secure mechanical connection and generally extends useful performance to higher RF frequencies.

Selecting a TNC Connector for Your Coax

A TNC connector must also be selected for the coaxial cable on which it will be installed. Cable diameter, center conductor size, dielectric dimensions, shield construction, and connector attachment method can all affect compatibility. A TNC connector designed for one cable type should not be assumed to properly fit another cable simply because the cables appear similar in size.

Common RF Cable Ferrule HEX Crimp Die Sizes*

.429" — LMR-400, RG-8, RG-11, RG-213, RG-214, Belden 8214/9913
.255" — LMR-240, RG-6, RG-8X, RG-59, RG-62, RG-223
.213" — LMR-195/200, RG-58, RG-142, RG-400
.178" — LMR-100/110, RG-174, RG-178, RG-188, RG-196

*The hex crimp sizes shown are nominal sizes. Always verify the required crimp dimensions with the connector manufacturer when the correct size is not known. Connector dimensions can vary between manufacturers and individual connector designs.

The majority of our brand center RF pins are designed to be soldered rather than crimped.