Chassis CTC121J , Model FKR2018T. OK, Its fine until it gets a reddish raster, and bright screen w/ retrace lines, then shuts down. Normal after a few minutes of being unplugged. Checked all soldering, Which caps should be changed?

Check the voltage on the red cathode. I brt it's 0v, or very low. Try unsoldering that pin from the CRT to determine if it's a CRT short, or a problem with the video output circuit. I would bet it's the CRT based on my experience with RCA CRTs. If it's a heater to cathode short, you can isolate the heaters and it iwll be fine. If it's a cathode to G1 short, you may be able to remove it with a CRT tester.

i wouldnt bet on a short in the crt on an rca set. zenith yes rca no. check the 200 volt screen source see what it is doing. there is usually a 47mf at 250volt cap in the rca chassis. might want to check that. steve