This two-transistor circuit was found in a 1966 US documentation. The power transistors are of the time. The system is intended for cars with contact breaker.
Found in English documentation from the 1990s, this circuit can employ equivalent components. The...
Found in an American circuit manual from the 1970s, this circuit can use any general-purpose transistor....
The diagram of this source appeared in a 1982 American publication, drawing attention to its...