Found in old documentation, this circuit makes use of amplifiers of the time, uncommon today. Next to the diagram, the formula for calculating the components.
This circuit activates an output, which can be a lock, only when a card containing the programmed code...
August 2017 - Texas Instruments is announcing the availability by Mouser Electronics of its new...
This circuit was obtained in a Popular Electronics of 1991. The magazine no longer exists, but the...