This circuit was found in a 90s Popular Electronics. It is based on a Motorola double timer common at the time. The circuit has a step for activating an external indicator. R1 and C1 determine timing interval.
This circuit was found in a 90s Popular Electronics. It is based on a Motorola double timer common at the time. The circuit has a step for activating an external indicator. R1 and C1 determine timing interval.