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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Missing pulse detector circuit using the 555 timer

Missing pulse detector circuit using the 555 timer

This 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 a expected pulse, which under normal conditions should be received at predefined intervals.

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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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