Can I repair the sound on my 1988 Mitusbishi Model #CK3514R?

I have the same TV. There is a switch on the back that turns off the speakers--it has gotten dirty. Just work the switch back and forth several times and the right channel should come back in.
The permanent solution, if you don't ever shut off the speakers, is to wire the switch permanently on by soldering jumper wires across the appropriate terminals.

Bob Kiessel
November 2006