Abstract: An apparatus for controlling a motor comprises an oscillator for providing a source of periodic signals, and a divider for converting the oscillator output into desired motor rotation frequency signals. A tachometer generates actual motor rotation frequency signals and a comparator compares the actual and desired motor rotation frequency signals and generates a rotation frequency error signal. The tachometer and the divider are coupled to the comparator. An SCR bridge controls motor rotation frequency. The comparator is coupled to the SCR bridge. An AND gate coupled to the source of periodic signals provides a counting gate during which periodic signals from any suitable source are to be counted and a counter coupled to the AND gate counts the periodic signals. A display displays the number of such periodic signals counted during the counting gate.

Abstract: A system for stabilizing the output of a voltage-to-frequency (V/F) converter having an input terminal and an output terminal. The system comprises a single-shot having an input terminal and an output terminal. The output terminal of the V/F converter is coupled to the input terminal of the single-shot. An integrator comprising an operational amplifier is coupled in integrating amplifier configuration for coupling the output terminal of the single-shot to the input terminal of the V/F converter. The operational amplifier comprises a difference amplifier. The integrator includes a capacitor coupled between one of the input terminals of the difference amplifier and the output terminal of the difference amplifier. The output terminal of the difference amplifier is coupled to the input terminal of the V/F converter.