Found in a 1965 CQ magazine, this circuit uses period components. The unijunction transistor can be a 2N2646 and the relay has voltage according to the supply.
This interesting circuit was found in a 1967 Japanese documentation. Transistors are types of...
This assembly circuit using a small motor as a generator was found in Radio Electroics magazine from...
This circuit is of great use today, when solar energy is becoming increasingly important. The...