The control circuit in Figure 1a allows you to manually adjust the power delivered to a load. By changing the setting of potentiometer R 3, you change the phase angle at which the thyristor (Q 3) ...

The ubiquitous 1971 digital miracle—the 555 Timer ... will have the circuit load “on” for half the time. In this project, we’ll apply a variable PWM signal to control the intensity ...

Several years ago [Michael Davis] built a charge controller for his wind ... he realized that most of his original circuit could be easily replaced with a 555 timer. Since the 555 chip is so ...

This DC power supply controller is controlled by pulse width modulation PWM, generated by the circuit around timer IC2 7555 according to the formula: Duty cycle = ((R1 + (VR1/2)/(R1+R2+VR1)) x 100% ...