Abstract: The first monostable multivibrator of a series connected pair of monostable multivibrators is responsive to each break interval of input dial pulses for establishing a fixed time delay after which the second multivibrator initiates a corrected break interval and starts a first timing capacitor thereof charging at a rate set by a fixed time constant. Each input break interval also causes a capacitor of a second timing circuit to start discharging at a rate set by another fixed time constant, the time that the second capacitor starts discharging being a function of the pulse repetition frequency of input dial pulses. When the charge voltages on the two capacitors are the same values, the output of a comparator resets the second multivibrator to terminate an output break interval so as to cause corrected dial pulses in the output thereof to have a constant percent break.