hi all, this is my first instructable, i hope you enjoy, and if you have any questions dont hesitate to ask me either by sending me an E-mail (Ahmedyasserahmed@gmail.com) or simply comment and i will do my best to answer all of your questions.
in this instructable i will explain how to build a simple 555 circuit that will blink a led and sound a buzzer, this has many application for example you can connect an LDR between the power source and the circuit and then put it in your closet where it is dark and when someone opens the closet the alarm will sound, or connect it to a transistor LDR circuit (which i will explain how to build in another instructable) and put it next to your door so if any one passes by the LDR his shadow will cause the alarm to sound.
Materials that are required:-
1- 10 kohms resistor
2-4.7 Kohms resistor
3- 470 ohms resistor
4- 555 IC circuit
5 Jumper wires
7-capacitor (47 uf)
9-Battery and holder (rpeferably 9v but anything between 5-12 will work)
Step 1: Connecting the Brain
Step 2: Connecting the Capacitor
Step 3: Connecting Pins 2 and 6
in a breadboard there is a gap between the 2 sides in the power supply row be sure to connect them (look at the photo)
Step 4: Pins 4 and 8
Step 5: Resistors Time!
Step 6: Next Resistor
Step 7: One Last Resistor
Step 8: Connecting the Led
Step 9: Connecting the Led to the Brain
Step 10: Connecting the Buzzer
Step 11: Feeding the Brain
by now yoyr breadboard is ready. lets connect the power
Step 12: Finishing Up
And there you go attach your battery.
Step 13: Working and Troubleshooting.
if you want it to be light sensitive connect an LDR between the battery and the circuit.