The update I forgot I promised��: I got the cover off, checked the belts, commutator, brushes, and all were fine and almost new. Checked the reaction when turning the screw on the bottom of the foot control, no improvement. Took the foot control apart and checked the length/connection of the carbon points. They were fine. Based on comments I have come across, I was unusually fortunate to get it back together without breaking those very fragile points! Plugged it in with cover off and watched operation as I controlled the machine. High speed only!
I found a couple very helpful forum conversations about replacing the capacitors and resistors that made it sound doable. I looked up parts and seemed very reasonable in price. Then I got real with myself about where I would find the time to practice soldering/unsold ring and then do the touchy work on the pedal. I opted to buy a generic replacement electronic foot pedal, cut the cord from the old and rewire it. I was going to have the local "authorized" Bernina tech do the job, but he's a kid who promised to do it that evening or next morning latest. Two days later I took the machine back and bought the part from him to do it myself.
Now the machine sews slowly, but hums before starting slow. At least it's usable!
Here is link to electronics discussion if any interested. I still plan to fix it one day!
https://electronics.stackexchange.co...290-foot-pedal
https://howtomendit.com/answers.php?id=91605