| 摘要 |
PURPOSE:To make it possible to know the time without observing the letter dial by generating the time broadcasting sound of the number at that correct time. CONSTITUTION:Signals from an oscillator 1 are subjected to frequency division at 2 to produce second signals, which are fed to second, minute and hour counters 3, 4 and 5. The outputs of the respective counters are decoded at 6 and displayed at 7. When the correct time is detected at 11, n is preset in a counter 12, and the second pulses are fed to the counter 12 and AND circuits 14 and 15. Then, alternate signals of 512 Hx are interruptedly generated from the circuit 14, and alternate signals of 1024 Hz are generated from the circuit 2 through the circuit 15 in a similar manner. The signals thus generated are fed to a speaker 18 through an OR circuit 16 so that the time broadcasting sounds at that time are generated. |
