"My luck has usually been the appliance repairman will tell me to buy a new applicant and I have to cough his high fee and buy a new appliance."

That is my fear.  That is why I am asking. 

I figure it is probably some switch or sensor that has gone bad. I looked online yesterday at a parts catalog. Some of the parts for this range are no longer available.  That is factoring into my decision.

My mom kept her oven for 40-some years before she replaced it.  Yeah, that has crossed my mind. I wonder if an appliance made 19 years ago is better made than a new one today. How do you know?

Final point: Last time I had the repairman out for this range, he told me to just buy a new one. That was 16+ years ago.