In this Instructable, you will learn how to make a double flash circuit, or a 'Blink, Blink, Pause' circuit.
Step 1: What You Need
You will need:
2x 555 Timer (You could also use 1 556 timer)
1x Resistor for Timer #1 ( I used two, valued 8.2k and 1.3k ohms, and connected them in series to get the value I needed)
2x Resistors for Timer #2 (I, again, added up two resistors, both 8.2k ohms, to get the value I need for resistor 1, and used a 100k resistor for the second one)
1x Capacitor for Timer #1 (I used a 100 micro farad capacitor)
1x Capacitor for Timer #2 (I used a 3.3 micro farad capacitor)
1x LED (Any colour)
1x 9v battery
1x 9v battery clip
Step 2: Placing the Timers
Start by placing the two 555 Timers on the breadboard. Place them the same way around.
Step 3: Placing Components for Timer #1
Place your resistor(s) for Timer #1 between pins 7 and 8. If you have two resistors to add up, make sure they are added in series. Put a wire in between pins 5 and 6. To add the capacitor, place a wire on pin 6 going to an unused row on the other side of the timer. Connect the positive leg of the capacitor to this wire and the negative leg to pin 1.
Step 4: Testing Timer #1
Place an LED on the timer with it's positive leg on pin 3 and it's negative leg on pin 1. Connect the positive end of the 9 volt battery to pin 8 and negative to pin 1. The LED should turn on and then, after a while, turn off. If this doesn't happen, go back and make sure you connected the legs on the capacitor and LED correctly. If it still does not work, check if your resistors and wires are connected properly and not touching.
Step 5: Placing Wires for Timer #2
Place a wire between pin 1 of Timer #1 and pin 1 of Timer #2. Place another wire between pin 3 of Timer #1 and pin 8 of Timer #2. Finally, place a wire between pins 2 and 6 of Timer #2.
Step 6: Placing Components for Timer #2
Place the first resistor(s) between pins 7 and 8. Add the next one between pins 6 and 7. Remember to place resistors that are added together in series. Next, place the positive leg of the capacitor on pin 2 and the negative leg on pin 1.
Step 7: Completion!!
Place an LED on Timer #2 with its positive leg on pin 3 and negative leg on pin 1. Finally, place two wires from pins 1 and 8 of Timer #1. Connect the positive of the 9 volt battery to the wire on pin 8 and negative on the wire on pin 1.
Now watch your LED blink twice then stop!
Comment any questions below, I will try and answer them as best I can.
Thanks for reading!