We found this circuit in a 1985 documentation. The transformer is an old TV flyback that has an exposed part of the core, where 10 to 20 turns of common wire are wrapped.
We found this circuit in an old publication. The circuit can be implemented with modern equivalent...
This circuit with transistors from a 1995 publication. The circuit is powered by a voltage taken...
This tiny photocell-powered audio oscillator was found in a book on transistors from the 1960s. The...