RCA audio plug This is by far the most common type of audio/video terminal. This two-wire connection terminal was invented by RCA recording company as early as the era when the radio appeared. There is also a more old and stranger Call it a "turntable" connector.
The RCA audio plug adopts the coaxial signal transmission method. The central axis is used to transmit signals, and the contact layer on the outer edge is used for grounding. It can also be used to transmit digital audio signals and analog video signals. RCA audio plugs are generally marked in pairs in different colors: the right channel is red (the letter "R" means "right" or "red"); the left channel is black or white. Sometimes, the center and surround channel cables will be marked with other colors to facilitate the distinction when wiring, but all the RCA connectors in the entire system are the same in terms of electrical performance. Generally speaking, RCA audio plugs have left and right channels as a group, and each channel is a line in appearance.