Most newer DVD players are understandably built for compatibility with newer TVs. Knowing how to hook up modern DVD players with new RCA cables to older TVs with a RF plug-in is an important skill, saving you money on a newer TV for as long as that old one is still functioning. Adapting older TVs to new technology is relatively simple with some low-cost purchases; even if plasma screens are the latest trend, there's no sense in trading in that older cathode model just yet.
Purchase an RF to RCA modulator. This is sometimes called an RF to RCA adapter or converter box. Older televisions almost uniformly feature RF plug-ins, but some DVD players may require something other than an RCA adapter. If your DVD player uses RCA cables, it will connect using two to three cables. A yellow cable is used for the video feed. Red and/or white colored cables are used for audio feeds. If your DVD player does not use these types of cables, you need a different type of modulator.
Plug the TV into the modulator's jack labeled either "to TV" or "output."
Connect the RCA yellow-colored video cable to the "video in" or yellow-colored "input" port on the modulator.
Connect the red and white RCA audio cables into the ports labeled "audio in" or "input" on the RCA to RF adapter. If the ports are not color coded, they will typically be labeled "right" and "left." The red cable usually plugs into the right side and white conventionally plugs into the left.
Turn on the DVD player, TV, and modulator box.
Make sure you set your TV to the channel indicated in the modulator's instruction manual. In most cases, your TV will need to be set to channel 3 for the converter to work. Occasionally, channels 2 or 4 are needed.