We found this circuit in a 1991s PE Hobbyst Handbook. The circuit fires 10 LEDs that can control incandescent lamps according to their maximum current.
This powerful amplifier was part of commercial sound circuits from the 90s. The integrated circuit...
This circuit generates a control tone that serves to adjust amplifiers, check audio cables. The...
This circuit locks when the sensors are opened. The relay can be 6 or 12 V depending on the power...