A Time Delay Light switch circuit

This circuit is useful to illuminate locations where a light source of low power is needed. A closet, a car trunk, are good examples.

Automatic night light circuit with one LED

This automatic night light circuit with an LED is simple, interesting and very easy to do. The circuit allows a better understanding of the operation of a phototransistor and thus be able to use it in other applications.

Car battery monitor circuit using 4 LEDs

This simple Car battery monitor, allow us to know the voltage of the battery at all times. To achieve this 4 leds are placed somewhere on the dash of the car. Each LED has a label indicating the battery voltage at that time.

This 2 LED Temperature change indicator shows us, by means of two LEDs, when the sensed temperature is above or below a set limit.

When the temperature is above the pre-set temperature level, LED D1 will light up and if it is below, LED D2 will light up.

Doorbell for Deaf People.

When a deaf person is alone in a house, it would be very difficult to realize that someone is knocking on the door without any visual warning signal.

Two-way traffic light Circuit using 555 and CD4017

This Electronic two-way traffic light circuit achieves the functionality of a typical two-way traffic light using a 555 timer and a CD4017 decade counter.

Battery Charge Monitor Circuit with LM3914 IC

This battery charge monitor shows, with colored LEDs, the charging process of a typical 12-volt car battery using the LM3914 Dot / Bar Display Driver.

6-LED VU meter using one transistor

This simple 6-LED VU meter allows us to visualize the level of an audio signal. Due to its few components, it is a cheap circuit and easy to build. Components are very common and very easy to obtain.

LED Sequencer using 4017 – LED Chaser.

This Circuit has 10 LEDs connected to the 4017 decade counter outputs. LEDs light up in sequence. Only one LED is ON at a time

Twilight switch circuit with Op. Amp.and LDR

This Twilight switch circuit activates a light, a lamp, a motor, etc., at the time of sunset and performs the reverse process at dawn.

This is an ideal circuit for activating a security light that must be on all night.

Bike Flashing LED Lights Circuit

Bike Flashing LED Lights Circuit. If you’re a cycling fan and you like biking, night and day, this useful circuit will make you to be visible and safe

Light-Emitting diode connected to 120/240 VAC

This circuit shows one or two Light-Emitting Diodes connected to 120/240 VAC. The reduction of the AC input is achieved using a capacitor and a resistor