How to Make a Fast Blinking LED Bike Light





Introduction: How to Make a Fast Blinking LED Bike Light

About: ______________________ One of my favorite inventors, and one of the most brilinat minds that ever walked the Earth is Nikola Tesla. Here are some Teslas q...

In this Instructable I will show you how to make a simple fast blinking LED light that you can attach to your bike or any where you want. It blinks more than 3 times in a second.
It is cheaper to make one than to buy one.
You can make it whit your favorite LED color,red,green,blue,yellow,RBG...
This was my first electronic project, so I recommend it to all beginners in the interesting field of electronics.
This bike light is easy to make,looks cool and most importantly, effective!

Step 1: Components

For your fast blinking LED you will need:

1. LM 555 timer chip

2. 180 K ohm resistor

3. 330 Ohm resistor

4. 0,22 uF, 16V or 100V capacitor

5. 9V battery snap

6. 9V battery

7. LED (go to step 2 so I can help you choose which one)

8. Circuit board

9. Plastic housing for electronic circuits



Step 2: Choosing the LED

There are lots of LEDs out there. 10mm,8mm,5mm,2mm,red,blue,green,yellow,UV.......

For this project I suggest 10mm LEDs, which color is up to you.

Here you can buy LEDs

Step 3: Tools

You are going to need some tools to do this project:

1. Soldering Iron

2. Solder

3. Vacuum for desoldering (just in case)

4. Wire cutter

5. Wire insulation stripper

6. Scalpel

7. Sand paper

8. Screwdriver

9. Telephone wire

10. Something to make a hole in the plastic housing (a drill)

Step 4: Makeing the Circuit Board Fit

Cut the circuit board so it can fit inside your plastic box. Use the wire cutters or a scalpel.


Step 5: Cut the Plastic Box

Peel of some of the plastic on the side (the longer side) of the plastic box. Use the scalpel and the sand paper. The opening should be 1mm wide, just for the wire from the LEDs.

Step 6: Make a Hole

Make a hole on the side of the box. The hole is for the switch. Use a drill or anything that can make a hole.

Step 7: The Electronic

OK. First I will give you the schematic, electronic plan, and in step 8 i will explain it.

Step 8: Connecting It All Together

Solder the 9 V battery connector where the battery is shown, with the negative (black) wire to pin 1 and the positive (red) wire to pin 8. We'll refer to these points later as "Ground" and "+9 V" (photo 1 and 2)

Pin 8 is connected to pin 7 through a 180 kilo-ohm resistor, and pin 7 is connected to pin 6 through a second a 180 kilo-ohm resistor. (photo 3 and 4)

Use a telephone wire to connect pin 2 to pin 6. (photo 5)

The 0.22 uF capacitor connects pin 6 to pin 1. (photo 6)

Pins 4 and 5 should be left unwired.

Pin 3 is our "clock" output

Solder the LEDs to the board and connect them together. Example: If you have 6 LEDs the positive (+) pin of LED 1is connected to LED 6 through the positive pins of LEDs 2,3,4 and 5 to the 6th LED (photo 7)

Take the output from the 555 (pin 3) and connect it to the positive side of the LED, through a 330 ohm resistor, and then to the ground (-).

Step 9: Attach the Switch

OK. You are all most done. Now attach the switch. Cut the wire from the battery snap, peel of 1mm of the wire on both sides and connect it to the switch.

Step 10: Put It All Togother

Push the switch through the hole in the plastic box, attach the board to the box and close it.


It is finished. Go ahead and attach it to your bike or what ever. Hope you enjoy my Instructable. Go easy on me, this is my first. Please leave a comment.



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     I'm thinking of making, like, making arrows on the back of a jacket for turning signals when biking. How would I figure out the resistor values for the 5mm leds on ebay I would buy?

    6 replies

    To start with dont touch Ebay LED's they are very poor and not worth bothering with for safety lights go to a good retailer and pay around $1 per LED much better brighter and last longer MUCH longer if you want resistor values google there is a page out there with a formula to calculate this just can not remember where it is sorry

    E-Bay/Amazon resellers usually buy the cheapest LEDs from China.

    I live in VietNam and the cheapest (ungraded) LEDs are sold by the kilogram, as are the lowest quality graded LEDs.

    The best quality are graded and sold by the 'each' price. Bright Red 3mm LEDs are going for 10 for USD$00.01 (1 cent) today.

    WTF! i buy all my LEDS from ebay. most retailers also get LEDS from same or similar manufacturers as ebay sellers.

    and seriously $1 per led... i buy 20 at that price.. if 18 of them die ive still saved money!

    BTW.. Ive never had any die unless i was doing something stupid with them e.g. 5v into a 3.6v led

    Ive used quite literally 1000's over the years

    I started when ebay led's were 70c each

    u pay $1 for LEDs?!?!? WOW! to me, even $0.50 is OUTRAGEOUS! i searched the internet top to bottom to find the cheapest LEDs. finally, i found this website had: LEDs, Resistors, Prototyping Boards. Capacitors, and WAY more. the AMAZING thing about this website is that LEDs are anywhere from $0.02 to $0.06. Although the items you order are coming from Bangkok, the shipping is EXTREMELY fast and cheap.

    I just wanted to let you guys know, that way you can buy more for less.

    Depend on what circuit you use?
    If you are using my circuits, the resistor values are the same...
    I think you have an Instructables just for the project that you mentioned.

    I made this and fitted it to my motorcycle helmet so even crazy Vinasun taxi drivers can see someone is in front of them!

    How can i turn it into a 5v supply circuit ? i wish to use it on a usb power bank.

    can we slowdown the time of the blinking of L.E.Ds.

    I made it but its too fast !!

    1 reply

    please explain to me how you made it!! please I'm begging you!

    Can I connect 4v rechargeable battery


    i wanted to ask that why 5mm res and blue LEDs don’t glow simultaneously when connected together but glow perfectly when connected individually. i need an awnser fast please..

    1 reply

    Ok so the reason the 5mm res and the blue LEDs wont glow simultaneously, I've had the same issue. its the voltage the two different LEDs need aren't the same. I don't get why but that's just how they are made. So i got this box of LEDs and so all the LEDs worked fine except for the yellow and the red LEDs. Later on I figured out the yellow and red LEDs work on 2.2 volts. the others LEDs were on 3 volts. So the two LEDs work on separate voltages so it "Trips" the timer and doesn't blink at the right time. Hope that helps! Sorry its been a Year XD

    plz can i use a 0.47 uf capasitor? ???

    Can you please upload video so that we can see how it looks while blinking?

    Could I use Texas instrument tlc555ip timer chip instead?