Hi Fred:

It sounds like you have become one of us, and you have one of those rigs
that things get worse and worse, instead of better and better, the more you
work on the problem.

One common alignment technique is to align somewhat inside of each dial end.
That will often give you a better overall alignment. Heath may not have
specified that technique, in an attempt to keep you in the band. But, you
should not trust the dial calibration when you get near band edge (and what
used to be a pink ticket).

Oscillators go out of oscillation for a reason. It can be that the
frequency limit of the transistor (or other component) has been reached.
That usually does not apply to a solid state circuit that has been working
fine for decades, although it can happen with tubes. It can be a change in
feedback. If it occurs just after you made some mechanical changes in the
capacitor (or any other component), take a hard look at that component. In
the case of the variable capacitor, the capacitor depends upon one or more
wipers making good contact. If they do not make a good contact, the
capacitor will not be doing its job. Oscillations can either change
frequency or stop.

The good news is that when you are able to correct the problem, there is a
great deal of satisfaction. Sometimes, you can do it better than the
original design team (which included the bean counters, of course).

73, Colin K7FM