Note: This is my first instuctable and i'm not a native english speaker - so please excuse my mistakes.
Step 1: Parts You Need
- 1 CMOS 74C14 - its a small and really cheap microchip, we use it to create oscillators to make our LEDs blink
- some jumper wires
- a breadboard to stick the parts on it
- a 9V block battery with batteryclip
for further experiments a potentiometer around up to 1 M
for every LED-Circuit (you can add up to 6 to one chip) we need
- an LED ;-)
- a capacitor (around 4,7 µF, you may vary the value to get different blink frequencies)
- a resistor 100k-200k
- a resistor to limit the led current, around 1-3k
Step 2: Okay Lets Stick It Together
Connect pin 7 of the chip with the ground (-) and pin 14 with the VCC (+)-bus on the breadboard.
Now connect the capacitor to pin 1 and the ground (attent to the direction, there is a minus printed on the Cap - that lead goes to the ground). Place a 100k-200k resistor between pin 1 and 2 of the chip. Then you need to add the series resistor (1-3k) between pin 2 and the LED. Attent to the right direction of the LED. The shorter leg goes to the ground.
I hope you may see it on the image.
If youre done, connect the batty to the plus and minus bus of the breadboard and your first LED should start blinking. :-)
Thats fun! Lets go forward, add more LEDs...
Step 3: Add More Lights
You can use every circuit for your blinky thing, so you may have up to 6 blinking LEDs on one chip. Attend to the direction. The first trigger goes from pin 1 to pin 2. On the other side of the chip the direction is mirrored. So it goes for example from pin 9 to 8.
If you do this on a breadboard be careful to avoid shortens between the parts!
Step 4: Get More Control
So with the big resistor (100k-200k) you can change the blinking frequency. Place a smaller resistor there, you may see the LED blinks faster. The smaller the resistor, the higher the frequency. You may also change frequency by changing the capacitor in the same way.
So if you want to have totally control, you may add a potentiometer instead of the resistor. So you can change frequency in realtime ;-).
Step 5: Get Creative
I made this blinky geeky tabletop decoration based on the circuit:
Thanks for reading. Have fun with building!