Depends on the model and chassis version of the RCA you have. The most common failure on recent projections from RCA were the use of non-leaded solder on the high voltage transformer causing intermittent voltage drops which then caused little pico fuses in the convergence circuit to open. To fix these sets properly you need to remove all of the non-leaded solder from all the pins of the high voltage transformer and then resoler with 60/40 solder. Then you will need to check the pico fuses that are near the transformer with an ohm meter to see which one opened.