This circuit was found in the September 1972 issue of Radio Electronics magazine. The circuit uses an operational amplifier of the time and a symmetrical 9 V source.
We present a circuit formed by six voltage comparators. Each comparator will analyze the voltage...
This circuit can generate time base signals from 5 to 1500 Hz. We find it in a documentation about old neon...
In this circuit the CA3140, an operational amplifier, is used as a comparator with the zener diode...