How to Convert CATV Cables to S-Video

by Jeff Grundy Google

    Most televisions sold today offer plenty of input options for connecting cable boxes, DVD players and other components. However, this is not usually the case with many older TVs sold before the beginning of the HDTV revolution, which sometimes shipped with only screw terminals for an antenna, a coaxial connection and an S-video interface. Consequently, if you want to connect an older TV to a modern digital cable box or DVR, you may find that the new device offers plenty of port options but not an S-video connector. To connect an older TV with an S-video port to a modern set-top box or directly to cable, you must you use a converter device.

    Step 1

    Power off the TV and cable box or other video device you want to connect to the television. Connect one end of an S-video cable to the TV and the other end to the “S-Video Out" or "S-Video" port on the RF modulator.

    Step 2

    Connect the RCA A/V cable set that ships with the RF modulator to the “Video,” “Audio Left” and “Audio Right” ports on the device. When connecting the cables, match the RCA plugs on the cables with the matching colored ports on the RF modulator.

    Step 3

    Connect the RCA plugs on the other end of the A/V cable set to the matching colored ports on the cable box, DVR, DVD player, game console or other video device.

    Step 4

    Connect the power adapter into the "AC” or "Power" port on the RF modulator, then plug the end of the power cord into an electrical socket.

    Step 5

    Power on the cable box, DVR or other player device, then turn on the TV and RF modulator. Insert media if required and then press "Play." Otherwise, use the cable box remote control to change the channel to view programming on the TV.


    • S-video does not transmit audio signals. Consequently, to hear sound for programming or videos you stream to an older TV with an S-video cable, you must connect the cable box, DVR or other video player to an external amplifier or set of powered speakers. To connect the cable box or video source to the amplifier, use a 3.5mm-to-RCA "Y" adapter cable.

    Required Items

    • RF Modulator

    About the Author

    Jeff Grundy has been writing computer-related articles and tutorials since 1995. Since that time, Grundy has written many guides to using various applications that are published on numerous how-to and tutorial sites. Born and raised in South Georgia, Grundy holds a Master of Science degree in mathematics from the Georgia Institute of Technology.

    Photo Credits

    • Thomas Northcut/Photodisc/Getty Images