Here is an oscillator circuit using two monostable circuits

Here is an oscillator circuit using two monostable circuits. Could someone tell me how to adjust the frequency and duty circle of this oscillator? Thanks!

VC 5V R1 47kQ C1 100nF R2 C2 16 U1A 100nF VOC 1RTCT 13 1CT 1A. 1B 12 1CLR GND SN74123N 6 U1B 2RTCT 2CT 20 2A, 12 2B 20 ci 2CLR SN74123N

Solution

SN74123N is a multivibrator IC from Texas Instruments. When given a low level trigger on input A or a high level trigger on input B, it generates a pulse output at Q whose width is determined by external resistor and capacitor. To realize an oscillator using multivibrator, feedback is being utilised in this circuit. Output of first multivibrator is fed to second where it works as trigger input. The output from second multivibrator is fed back to trigger input of first one. A small disturbance triggers the first multivibrator, whose falling edge triggers the second, whose falling edge again triggers the first and the cycle goes on.
The frequency of the output oscillations are determined by the pulse width of the first multivibrator. If it\'s pulse width is high, it will take longer for the second multivibrator to trigger. Thus by changing the pulse width of first vibrator we can change the output frequency. To change the pulse width, replace the resistor R1 with a variable resistance such as a potentiometer. By varying it\'s resistance, we can vary the pulse width of first multivibrator and hence the frequency of the output pulse.
To vary the duty cycle of output pulse vary the second resistor R2. Replace it with a potentiometer. Varying this resistance will vary the pulse width of the output pulse and hence it\'s duty cycle.