RCA Colortrak 2000, No Red

[compucat]

To produce yellow, the red and green have to be in correct balance. The absence of red or green will render the set unable to produce yellow. Try turning the color control completely down (counterclockwise). A properly working set will give a black and white picture at this point. What color is the overall picture? If the red gun is not operating, the picture will have a cyan (light bluish green) appearance. If red and green are both out, the picture will be blue. This will help to determine exactly which gun or associated circuitry is at fault so you can look in the right direction.