requency in) Refers to coaxial sockets on the back of older TVs, VCRs and DVDs that accepted analog video signals. The "RF in" socket is typically receiving VHF/UHF signals from an antenna. Contrast with RF out
. See F connector
The "IN" jack on this VCR receives VHF/UHF TV from an antenna. The "OUT" jack sends signals converted to TV channel 3 or 4 because very early TVs had only antenna inputs.