This circuit was obtained from a 90s Radio Electronics. The value of R1 determines the scale according to the table next to the diagram. The power suppley must be symmetrical.
This circuit was obtained from an American publication of the 80's. The integrated circuit is of the...
This circuit activates a piezoelectric buzzer with an oscillator at the end of the programmed...
This circuit was found in an Electronic Design from the 90s. The integrated circuit is from that...