Jock Cooper wrote in message ...
Hi everyone,
...
How do you diagnose a bad
oscillator circuit?

Roy offered some good advice. No need for me to try to duplicate it!
But I know there can be a lot of times you just don't see something
that would be obvious to someone else who has more experience. If you
can find someone locally to have a look at things, the answers might
come a lot quicker. Failing that, if there's a place you could put up
some pictures on the web, that might help.

Are you using known-good circuits? Sounds like you probably are,
given that you understand the differences among the various types of
circuits. But it might be good to get your hands on a book with a
bunch of circuit ideas in it, if you don't already have one (or more).

Cheers,
Tom