If the quality of your TV picture has deteriorated and you've checked that your TV antenna is positioned correctly, then you should check the wiring of your antenna. You receive the TV picture through your antenna and the signal is transmitted to your TV through coaxial cable. Coax cable is simply a central wire core, covered with plastic insulation and an outer wire mesh screening. The complete cable is covered in a protective plastic layer, the same as most other cables. The only parts that occasionally require maintenance are where the coax cable joins the antenna, or the coax plug that goes into your TV.
Check the coax plug connected to the back of your TV before checking the wiring on your TV antenna. It's the easiest part to check and may provide a solution to the poor quality of your TV picture.
Hold the plug and gently pull the coax wire to see if it moves. If it appears loose you need to rewire the coax plug. Follow the instructions in Section 2 for rewiring a coax plug.
Check the connection to the antenna. Some are connected with a coax plug; others are connected using screw fittings. If it's attached using a coax plug, repeat steps 1 and 2. If your antenna is located outside, check the plug for corrosion. Replace a corroded plug by following the instructions in Section 2.
Check the wired connections to the antenna if they are attached by screws. If the wires appear loose, have detached, or show signs of corrosion, you need to rewire your TV antenna. Follow the instructions in Section 3 to rewire the antenna.
Remove the coax plug cover then remove the clamp holding the wire mesh screening. Discard the coax plug and use a new one; they cost a few cents.
Use a sharp knife to cut cleanly through the coax cable several inches away from the end. Check the end of the cable to ensure that the internal wires are clean and bright. If not, cut another inch or two until you find a part of the cable that appears "new." Remove a half-inch of the outer plastic coating by running a sharp knife round the cable. Don't cut too deep as you will cut into the wire mesh.
Slide the exposed wire mesh up the cable so it forms a neat circle of wire at the neck of the protective plastic. The insulated central core is revealed. Cut a quarter-inch off the insulation and you are left with the central metal wire. This carries the picture and sound to your TV.
Locate your new coax plug and remove the cap. There is a winged clamp inside. Slightly open the clamp and slide it over the cable until it covers the wire mesh. Firmly squeeze the clamp together so it fits tightly over the wire mesh. Cut any exposed strands of wire.
Hold the base part of the coax plug. Insert the central wire into the pin. Push down until the clamp touches the outer rim of the plug. Slide the cap down the cable until it touches the plug, then screw the two together tightly with your fingers. Connect the coax plug to the TV or antenna, depending which one you replaced. If both ends needed rewiring, then plug both ends in. Switch on your TV and check the picture.
Remove the cover protecting the screws and wire fittings on the antenna. Unscrew both screws. Make a note of where each wire attaches. The wire mesh will be attached to the larger screw and is usually marked "ground."
Clean the antenna fixings with a wire brush to remove any corrosion. If the screws are too corroded, replace them.
Cut through the coax cable at a point where the cable appears in good condition. Remove a half-inch of the outer plastic coating by running a sharp knife around the cable. Don't cut too deep as you will cut into the wire mesh.
Undo the wire mesh and twist it to make a length of wire. Cut a quarter-inch off the inner insulation so the central metal wire is exposed.
Reconnect the coax wire mesh to the screw labelled "ground." Connect the central wire to the remaining screw fixing. Check for tightness. Replace the cover and check your TV picture.