This circuit is from an old American publication, using transistors of the time and operating with a 48 V power source. The load is 2.2 ohm, and the transistors must be replaced by modern equivalents.
This circuit maintains on a flashing LED at a frequency determined by the capacitor. The...
After starting, this circuit turns off the relay in a time that depends on the 4020 pulse-count. This...
This sophisticated circuit is from a 1975 documentation. The components are from the time and the...