This immobilizer circuit for vehicles was found in a 80’s Hands On Electronics. The circuit shortens the platinum to prevent its operation and thus the operation of the engine when started.
This circuit was found in an American publication from the 50's. The transistors are made of...
The circuit shown is an amplifier for medium impedance headphones including bass and treble...
This circuit for an optical audio link using LED or LASER was found in a 90s QST magazine. The circuit...