This circuit was found in a 1971s English magazine. We can still assemble it using BC548 transistor. The other components are common. The supply voltage of 6 or 12 V depends only on the relay.
This precision circuit was found in ancient American documentation. The most critical component is the...
This circuit drives a load with a delay given by the RC timing components. The circuit is from...
This project is from a 1982 documentation, based on an astable multivibrator with two transistors. The...