We found this circuit in an old magazine. This is an assisted ignition, where the contact breaker is kept. The circuit uses transistors that are uncommon today. Equivalents can be tested.
This circuit generates the busy tone of ordinary telephones. The transistors can be the BC548 and...
This small 1 W amplifier uses a Motorola integrated circuit from the 1970s. The integrated circuit...
This is a configuration widely used for oscillators with crystal from 1 to 20 MHz typically. The...