Suggested by Motorola documentation from the 1980s, this circuit can be implemented with equivalent power MOSFETs. The type depends on the current of the controlled motor, as well as the diodes.
This commercial circuit is from a Japanese magazine from 1967. It uses germanium transistors, and...
This circuit can be used to drive relays, solenoids, motors and other loads according the...
This circuit is based on the small keychain that responded to the sound of a whistle and were...