We found this circuit in an American documentation from the 80s. The integrated circuits are operational amplifiers of the time. We can test modern comparators like the LM339.
The existence of field effect transistors at the input of the integrated circuit (operational...
This circuit generates a siren sound. It was found in the April 1969 Radio Electronics magazine. The...
Suggested by Siliconix in documentation from the 90s, this circuit can present gains of digitally...