This circuit that we found in a 1990 documentation uses an LED as a sensor. The operational amplifier is equivalent to the 741 and the trigger adjustment is made in the potentiometer.
This intercom for the 27 MHz band was found in a recent English documentation, working with a...
This simple circuit allows you to control remote control servos that operate with pulses. The...
This circuit consists of a variation of the previous one being activated when the switch is...