Abstract: A circuit arrangement for storing the phase of an a-c voltage which stores the original phase with certainty even if the a-c voltage disappears or in the event of an abrupt change of the phase, in which two monostable multivibrators have outputs which are connected to each other via logic circuits. The logic circuits also having as inputs pulses corresponding to the negative and positive half waves of the a-c voltage, with a control arrangement controlled by the a-c voltage coupled to the logic circuits to control which of the two sets of inputs is effective to trigger the monostable multivibrators.