Music box circuit using a CD4017 decade counter and two 555 timers.

This circuit attempts to emulate the operation of a music box. The maximum number of notes is 10, allowing us to make a simple melody.

Automatic night light using 555 and relay

This Automatic night light using 555 IC turns lights on when there is no daylight. The circuit is perfect for lighting single places such as the garden, the front door of the house, the entrance to the garage, etc.

Electronic sound control circuit (applause)

This electronic sound control circuit works like a sound activated relay and can activate or deactivate a device connected to it, by two consecutive claps.

Electronic Music Metronome circuit using a 555 timer

This Electronic Music Metronome circuit, allows those persons who study or are music fans, to keep the timing, quite accurately.

With this sound activated flash circuit, you can achieve incredible pictures of the most unexpected moments.

Pictures like a water balloon that just burst and the water still floats in the air, or when an object of any type explodes.

Missing pulse detector circuit or No pulse detector circuit.

This circuit is very interesting because it can detect or warn of the absence or delay of an expected pulse, which under normal conditions should be received at predefined intervals.

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

Time Delay circuit using Triac and 555 timer

This Time delay Circuit using Triac and 555 Timer is very useful when we want to activate or switch on, appliances or devices that works on alternating current (AC), after a preset time.

This darkness detector circuit beeps when the light drops below a certain level.

The main elements of this circuit are the 555 integrated circuit, working as an astable multivibrator and an LDR which is used as darkness sensor.

Police Style Strobe Light Circuit.

This circuit shows the familiar lights which are used on police cars. It uses a 555 timer as a clock for the 4017B decade counter, two transistors and twelve LEDs

Electronic Doorbell Circuit using a 555 timer and a CD4017 decade counter

This electronic doorbell circuit gives us all the possibility to change the tone of each of the 10 musical notes that the circuit can have. This means we can create our own sound sequence.

How to make a car temperature alarm?
This car temperature alarm check the car engine temperature and warns us, by means of a sound signal, when the temperature exceeds a seted value