PURPOSE: To obtain a prescribed phase difference between D/A conversion outputs, by frequency-dividing an input signal into n-stage, storing it as a digital value phase-shifted for a prescribed amount in proportion to a voltage and reading out the prescribed voltage from a reference memory and decoder when the voltage is applied.

CONSTITUTION: An input voltage applied to a variable resistor 1 is frequency- converted 2, frequency-divided 3 into n-stages and applied to a memory 41 respectively. A digital amount which is proportional to the input signal and phase-shifted from the input signal is stored in the address corresponding to the n-stage of a frequency divider 3 in the memory 41, the content of storage corresponding is stored, D/A converted 51, amplified 61 and trasformed 81 into a signal with the reference phase and waveform. An arbitrary phase command is decoded 9 and the corresponding output terminal is taken at L level. When a terminal 2 is at L level, a memory 43 is selected, the corresponding storage content is read out, D/A-converted 52, amplified 62, transformed 82 and outputted in parallel with the reference signal. Various phase differences are obtained between output of transformers S1 and S2 with the phase shift selection command.