This circuit activates a warning lamp when an incoming call is received. We found it in an 80s Hands-On Electronics. The diac and triac can be of any type.
This battery charger circuit was found in ancient American documentation. The components are...
Despite being a circuit found in an Argentine publication, it seems to us that the original is...
This circuit was found in a 1990 publication. The sensors are electrodes placed in the water tank...