DIY TV Balun
By Richard Asmus
If you want to connect an antenna with a coaxial connection to an older TV that uses a two-wire input, you'll need to use a balun transformer because these are different types of circuits. The coaxial connection is an unbalanced circuit that carries a single signal on its center conductor. The two-wire connection on your old TV is a balanced circuit which carries two equal signals traveling out of phase. For many applications, the balun requires a manufacturing process. But in the case of your old TV, you can do it yourself.
Use the knife to strip off the outer insulation from the coaxial cable 2 to 3 inches back from the end.
Use the tip of the knife to unbraid the shield back to the insulation. Be careful not to cut or break any of the strands.
Twist all the strands of the shield together to make them form a single wire.
Unscrew one of the terminals on the balanced connector on the back of the TV, wrap the shield around the screw, then tighten it with a screwdriver. Cut off the excess with the wire cutters.
Unscrew the other terminal, strip the insulation off the center conductor at a distance that allows wire to connect to the terminal with the insulation flush against it. Wrap the wire around the terminal and tighten the screw. Cut off the excess wire with the wire cutters.
- For a TV set that has a coaxial connection and an antenna that has a balanced connection, you can make your balun at the antenna end.
Richard Asmus was a writer and producer of television commercials in Phoenix, Arizona, and now is retired in Peru. After founding a small telecommunications engineering corporation and visiting 37 countries, Asmus studied broadcasting at Arizona State University and earned his Master of Fine Arts at Brooklyn College in New York.