PT Journal AU BALARA, M SO Trends in education PY 2009 BP 386 EP 389 VL 2 IS 1 DE Tachogenerator; analog memory; controller; control system; discrete control circuit. AB The speed control system of an externally-excited DC motor without tachogenerator (TG) is actually a discrete control circuit where the motor current is intentionally cut-off so that the induced armature voltage may be sensed. This voltage (proportional to the angular speed of a motor) is stored in analog memory during one sample period and processed by the speed controller. That's how the speed control of a motor without TG is carried out - angular speed is sensed by the motor itself. ER