Found in the May 1975 issue of Radio Electronics magazine, this circuit turns on after a certain amount of time. This gives the owner of the premises time to leave before the alarm is activated.
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...