I have probed my A701A and looked at one of the relevant patents. My ''provisional'' schematic is [https://hyperentang.wordpress.com/|here] .
As I say there, it is only guesswork based on probing with a simple multimeter without C and H ranges in circuit.
On my machine, it has become clear that the only problem was that the "points" (the centrifugal switch) no longer closed when the motor was not running. It was easy to remove the retaining screws and bend the copper support a little.
The relevant patent (best in pdf) is US3701935.pdf. I can't for the moment find where it was freely available, but avoid some of the suspicious sites that seem to want to charge or collect information to download it. That patent by Prof Collie is about adding a triac to the circuit precisely to reduce wear on the "points".