Abstract: A digital clock for giving acoustic time-indicating signals having an oscillator, a time integrated circuit driven by the oscillator, a first display element connected to the time integrated circuit to show hour and minute and, a second display element connected to the time integrated circuit to show a day among a week. A minute and a hour decoders are connected to the first display element to convert signals into a form of binary code. A memory unit receives the signals from the minute and hour decoders. A setting circuit has a number of flip-flops and control switches to be connected to inputs of the memory unit to pre-set a moment for giving acoustic time-indicating signals. An acoustic generator and a driving interface are connected to respective outputs of the memory unit and are driven by the memory unit to output the time-indicating signals.