It's a natural instinct to turn to the help of a trained television professional to handle the troubleshooting and repair of your Sony Trinitron TV. However, you don't need to open up your wallet just to free yourself of television problems. With nothing more than a large magnetic coil, you can troubleshoot your Sony Trinitron TV for a variety of potential issues even if you lack any prior experience with Sony TVs and electronic troubleshooting and repair.
Check your video input setting. You may have left the wrong video input selected after using an external device such as a DVD player, which would result in a blank Sony Trinitron TV and a lack of audio. Toggle through your video inputs using the "Input" button on the top left of the Sony Trinitron TV's remote. This should allow you to reselect the correct input and may alleviate the problem.
Check your audio and video cable connections on the back of the Sony Trinitron TV if you are still suffering from audio or video problems. The standard, included A/V cable for the Sony Trinitron TV is a RCA cable connection, which consists of six prongs, three on either end of the cable. Each end has one yellow, one red and one white prong. There are yellow, red and white ports for these prongs on the back of the Sony Trinitron TV and the rear of your cable or satellite box. Ensure that the prongs match in color with the ports they are connected to.
Look to see if there is any noise in the form of rapidly dancing white dots and other disturbances on your Sony Trinitron TV's screen. This is commonly known simply as "snow". Try tightening the coaxial cable on the back of the Sony Trinitron TV in order to reduce and wipe out the "snow" effect. This cable should not be loose in any respect, otherwise interference will likely continue to be a problem on your Sony Trinitron TV.
Look again at your screen and see if there are any irregular colored blotches on the display. This is likely a result of magnetization. Such magnetization may have occurred when an electronics device was left on top of your Sony Trinitron TV for too long, so remove any such device if applicable. Also, use a magnetic coil on your Sony to demagnetize the screen. Wave the coil in slow loops close in front of the display to remove the blotches. Make multiple passes with the coil in front of the screen if necessary. The blotches may also partially disappear over time on their own if the offending electronics device has been removed.