A plug and socket for a coaxial cable. They are found on all old audio/video devices and many new ones that continue to support analog signals. They are also used for digital signals (see S/PDIF).For decades, both RCA and mini-phone plugs and sockets have been the most widely used connectors on consumer equipment (see mini-phone connector).Also known as a "phono connector" because in the 1940s, Radio Corporation of America (RCA) designed it to wire an RCA Victor "phonograph" turntable to the radio to greatly amplify the sound. Only one cable was used as it carried a monophonic signal, not stereo. See A/V ports.