• 555 alarm / timer circuit [VERY EASYYY!!!]


    blinking depend on time constant which is tau = RC. try making tau greater than 1 second. you would be able to see the LED blink. Use 220 uF capacitor and a 100ohms resistor if you want to see the LED blink.

    Remove the buzzer and check if LED id glowing, if not try using lower capacitance value. 0.047uF worked for me

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