This circuit for very long-time intervals was found in the March 1993 Radio Electronics magazine. Times of several days or even weeks can be achieved depending on the value of C1.
This circuit found on a William Sheets can be used with a headphone or external amplifier. The...
In the figure we have the circuit of a complete audio generator using the 741. The circuit was found...
This monostable multivibrator with signals in phase opposition was found in October 1986 Radio...