The dream of openening a speedometer again

[9/17, 17:55] Dr. Harish Ravi: A speedometer is a motor as generator and voltmeter.. I would now like to open a speedometer and see how this is realised.. I saw a alumnium cylinder with magnet and spring in 1995.. I would like to verify what is what!

[9/17, 18:01] Dr. Harish Ravi: If there is an optimization of generator and voltmeter in 1 package..

[9/17, 18:14] Dr. Harish Ravi: I wanted to open a speedometer one more time after education..