Cricket, thanks for your suggestion, but I don't think it is the bobbin assembly, because I can turn the hand wheel manually, and it is smooth. I just can't get any power with the pedal -- not even bobbin winding. Wouldn't it be the case if the bobbin assembly were jammed that if the stop motion screw was turned to disengage sewing that the bobbin winder would move when power was applied?
My next step is to try to get a spare foot/knee controller from the sewing machine repair shop and try that. If that doesn't fix it, then I will need to bring it in, suspecting the motor to be the problem.
Today I did all of my sewing on the Singer 301, and it went ok. I am happy to have that option.