[Cruisin Marine]

Thank you so much to all the telephone experts who have offered advice and guidance. I've tried nearly everything you've suggested and I have learnt a lot. In this case, I've learnt that some things are beyond me and I am abandoning my 706 ringing problem. I'll be donating it to our local antique centre where someone else can carry on the good work.

Once again, thank you to everyone !!

Don't give up!
Many of us do not crack a nut at the first attempt, in fact, sometimes it takes many attempts over years to get the desired outcome.
One thing (a good thing at that) in radio design, repair or servicing is that patience is a virtue, sometimes when you go away from things your mind works best at a sub conscious level and finds the answer.