This 6-transistor radio was sold in Japan in the 1960s. The super-heterodyne circuit for the OM band was powered by ordinary batteries.
With the circuit shown in the figure, it is possible to connect or disconnect a load controlled by the...
This immobilizer circuit for the car was found in the Radio Electronics magazine of December 1976....
This fast converter using operational was found in a 70s American documentation. The circuit can be...