Phase detector and light self-test card A2 circuit

This handy little circuit can tell the difference between darkness and light, making it very useful for switching on and off signs, porch lights or other things when it gets dark or light. More: R1 Adjusts sensitivity The circuit described is...

Light Sensor including Photocell and LDR Sensor

Electronics tutorial about light sensors including photocells, LDR, photodiodes, phototransistors, photovoltaic cells, and light-dependent resistors. Light sensors are crucial components in various electronic applications, enabling devices to respond to changes in ambient light levels. This tutorial covers several types of light...

Light Controlled Relays

The first circuit energizes the relay when the light rises above the preset level. The second circuit energizes the relay when the light falls below the preset level. The two circuits are practically identical. The only difference between them is...

Quick On-Board Junction Tester

Short circuits or broken PCB tracks can be easily identified using a multimeter. However, this tool may yield inaccurate results when assessing the efficiency of a transistor or diode unless the component is unsoldered and removed from the PCB. Additionally,...

Automatic Night Lamp with Morning Alarm

This circuit automatically activates a night lamp when the bedroom light is turned off. The lamp stays illuminated until the light sensor detects daylight in the morning. A super-bright white LED is utilized as the night lamp, providing bright and...

Light-level-detector

If R, the sensor matching resistor, is equal to the "dark" resistance of the cadmium sulfide cell, the amplifier output will range from 0 to 2 as the light level varies from "dark" to "bright." The circuit operates similarly, but...

Light Pollution Meter

My circuit adds a transistor, to add feedback, and two resistors, to tailor the range of the control, with the result that a single-turn potentiometer gives a control range of about 2 to 30 microamps. I installed my circuit in...

LEGO Light SensorCircuit With LM358 IC

The following circuit illustrates a LEGO Light Sensor Circuit Diagram. This circuit is based on the LM358 integrated circuit, which features a dual operational amplifier and high-speed capabilities. The LEGO Light Sensor Circuit utilizes the LM358, a versatile dual op-amp IC,...

Light-Controlled Pond Pump

This circuit was designed to control a pump in a garden pond, enabling it to automatically activate at dawn and deactivate at dusk. The circuit utilizes a light-dependent resistor (LDR) to detect ambient light levels, which serves as the primary sensor...