Abstract: A control circuit for a closed loop command system having an output which is adjusted to conform with an input command level. A pulse generator provides digital pulses with durations representative of the output of the system. Command pulses are generated by the system pulses and have durations representative of the input command. Each pulse is applied to logic gating along with the complement of the other pulse, with the logic gating providing a signal indicating whether the system pulse or the command pulse is longer. The last gate signal is retained in a flip flop memory and is used to adjust the output power level up or down depending upon the result of the pulse length comparison.