This circuit was found in a Popular Electronics from the 90's. The components used are common and instead of the buzzer we can use an LED or a relay.
This circuit was obtained from an English magazine from 1976. The circuit operates two LEDs and...
Found in a publication from the 60's, this power supply has no regulation, but only current...
This circuit can use the LM148 and its more modern equivalents, generating a sinusoidal signal whose...