This circuit was published in an article in Radio Electronics magazine in October 1988. It uses components that are still common today, except for the sensor, which is a special type from that time.
This circuit acts as a NOR gate for LED drive from TTL outputs. The circuit must be powered from a 5...
This signal injector uses a single integrated circuit as an oscillator, producing rectangular...
12 V battery chargers provide higher unregulated voltage. With the regulator shown, obtained from...