Today's Mystery Guest (RCA CTC-4)

[dtvmcdonald]

Why not try a 3.58 MHZ signal from a signal generator? disconnect the
crystal, feed the signal from the generator to the no-longer
oscillator's grid and look on the scope at the two outputs of the
output transformer. See what happens if you vary the frequency around
3.58 MHZ (on the scope).

Another thing is to check the crystal ... connect the sign generator
to it with a 10K resistor and look on the scope. You should see the
sharp resonance as you tune. Remember that a previous thread had
what was thought to be a bad crystal; they tried two good crystals and
they didn't work. It was a bad part. After replacing the bad part
but leaving in a "good" crystal it didn't work ... but with the original crystal did.
So these circuits are picky about the crystal. If the crystal is bad, it may
be that only an exact replacement will work.