It sounds to me lile your oscillator might be misadjusted such that it
is oscilalting on the fundament rather than the 3rd overtone. If you
are lucky just tweaking the oscillator coil will snap it back to where
it belongs. As the other guy pointed out, though, the oscillator
might have been monkeyed with if some CB'er tried to modify it.

Also there is a better source for the TR4 manual, with better
schematics. Look for TR-4C_Manual.pdf on Google.

Rick K2XT