If you want simple meter the intensity of the light in a simple way. This circuit is very interesting, because with a LED display with 5 levels.The main equipment is uA741 the most popular op-amp circuit, to used the photo transistor is a device for receiver a lighting to change is electricity very low. We use IC1 acts boost up current, or to compare the voltage levels.The VR1 adjusts the offset voltage to the LED display complete , the intensity of light to measure.The power supply size use +9 V and -9V.
EmoticonEmoticon