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 90’s 303 Circuits. The components are from the period and the heating...
Suggested by Siliconix in 1980s documentation, this circuit uses currently uncommon components. The...
In this charger the current is limited by the incandescent lamp. Lamps from 40 to 100 W can be...