| 摘要 |
PURPOSE:To obtain a simple dual-tone generator of constitution that can generate a dual-tone signal only by one oscillator and one divider. CONSTITUTION:A signal of frequency (f) from oscillator 21 is applied to frequency divider 22, which frequency-divides the signal of frequency (f) to generate audible signal tones of different frequencies f/K1, f/K2 and f/K3. Through switch 23, signals f/K1 and f/K2 are sent to output line 24 by turns. Signal f/K3, on the other hand, is used as a switching signal for switching switch 23. A dual-tone signal obtained in this way is used as an alarm tone. |
