BNC Pinout
A bayonet-locking coaxial connector for video, RF, and test signals up to ~4 GHz.
Overview
BNC (Bayonet Neill-Concelman) is a quick-connect coaxial connector with a twist-lock bayonet coupling. As a coax connector it has just two conductors: a center contact carrying the signal and an outer shell carrying the shield/ground.
It is available in 50 ohm and 75 ohm impedance versions (the 75 ohm type is standard for SDI and composite video). The bayonet locking makes it popular for test equipment, oscilloscopes, and broadcast video.
Pinout
| Pin | Name | Function | Description |
|---|---|---|---|
| Center | Signal | VIDEO / SIGNAL | Center conductor carrying the RF/video signal |
| Shield | Ground / Shield | GND | Outer bayonet shell, coax shield and ground return |
Notes
- Available in 50 ohm and 75 ohm versions; 75 ohm is standard for SDI/composite video.
- Usable to roughly 4 GHz (50 ohm) depending on construction.
Reference: Wikipedia — BNC connector· verified 2026-06-27