This 50% active cycle TTL clock generates signals from 4 to 20 Hz. Its power must be supplied with 5 V and other frequencies can be generated with capacitor replacement.
This circuit was found in a 90s Hands-on Electronics. The transistor can be a BC548. What it does...
We found this circuit in the semiconductor ON manual using couplers of the time. These components...
This circuit was found in an old Radio Electronics, but can still be assembled as the components are...