Demos by PIRA

  5K40.10Rolling bar motor: Same as D+30+ 20.
  5K40.10Elementary split-ring armature DC motor. D+15+6 as a motor.
  5K40.20Generator: Coil with DC commutator rotates between magnets.
  5K40.20Alternator: Coil with AC commutator rotates between magnets.
  5K40.80Hand-cranked DC generator powers 120 volt lamp.
  5K40.80Hand-cranked AC alternator powers 120 volt lamp.