Darkness detector circuit with audio output using 555

Darkness detector circuit with audio output using 555

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.

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Electronic Doorbell Circuit using a 555 and CD4017

Electronic Doorbell Circuit using a 555 and CD4017

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.

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Car Burglar Alarm using two 555 timers

Car Burglar Alarm using two 555 timers

Car Burglar Alarm using two 555 timers

This is a simple Car Burglar Alarm circuit that uses a dual contact relay and two 555 timers, each of them working as a monostable multivibrator.

The alarm will activate the car horn, approximately 5 seconds after either door is opened and has not been properly closed.

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Refrigerator door alarm circuit with two 555 timers

Refrigerator door alarm circuit with two 555 timers

Refrigerator door alarm circuit with two 555 timers

This refrigerator door alarm circuit alerts you when the door has been left open. Very important, because the power consumption increases when this happends. It uses the popular 555 timer IC

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Time Delay circuit using Triac and 555 timer

Time Delay circuit using Triac and 555 timer

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.

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