[Boatanchors] Collins 75A2 PTO issue

[Tree]

Have an interesting problem with the PTO in my 75A2.

I did have to replace the feedback capacitor about a year ago.  It worked
fine until recently.  Now, I have a problem where it only wants to
oscillate nearest the lowest frequency (down between 1.8 and 1.9 MHz).  As
I tune up - the output gradually starts declining and then it totally
stops.  This might be getting worse over time.  Currently, I can't even go
50 kHz without it pretty much stopping.  It is very gradual - so not like
something is suddenly getting shorted.

Some of the caps have been replaced by a previous owner.  I will
probably just rebuild the whole circuit with new components if I can't
figure anything else out.

However, I thought I would ask here if anyone else has seen this and offer
any advice on fixing it.

73 Tree N6TR
tree at kkn.net