A "channel 3/4 output" was a common output selection for consumer audiovisual devices sold in North America that were intended to be connected to a TV using a radio frequency (RF) signal. This channel option was provided because it was rare to have broadcast channels 3 and 4 used in the same market, or even just channel 3 itself. The choice allowed the user to select the unused channel in their area so that the connected device would be able to provide video and audio on an RF feed to the television without excessive interference from a broadcast signal.