Electronic circuits that use the 555 Timer

555 Timer Circuits

555 Timers are fun and a great way to start learning electronics


A circuit that produces 5 different sounds.


This circuit produces a tone according to the button being pressed. Only 1 button can be pressed at a time, that's why it is called a monophonic organ. You can change the 1k resistors to produce a more-accurate scale.


Toy Organ Circuit


Coming Soon

Parts List

1x - NE555 Bipolar Timer
1x - 4.7K Resistor (1/4W)
4x - 1K Resistor (1/4W)
1x - 10K Potentiometer (1/4W)
1x - 10µF Electrolytic Capacitor (16V)
1x - 100nF Capacitor (16V)
1x - 8 Ohm Loudspeaker
1x - 9V Voltage Battery

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