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LED flashing circuit

LED flashing circuit
I will show you how to make a LED circuit that make LED flash at different intervals depending on the capacitor size.
 
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Step 1Materials

Materials
What you will need:
-Soldering iron
-Solder
-Wire
-2 1kilo-ohm resistor
-1 110 ohm resistor
-1 10 to 1000 uf capacitor
-Perf board
-1 or more LED's
-1 555 timer
-1 9volt battery clip
-1 9volt battery
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31 comments
Feb 21, 2008. 3:54 PMrandofo says:
Hello, and welcome to the Instructables community! It's great that you've decided to tell the world about something you've made by publishing an Instructable. We just wanted to let you know that your project still needs a little more work if you want it to be well received on Instructables. Projects that don't include certain basic elements tend not to get the attention that they deserve, and so we'd love for you to check out the list below of what makes a successful Instructable. Successful projects on Instructables include: - clearly written details of a finished project with instruction - as many steps as are necessary to explain your project - clear images that you took of your project for most, if not all of your steps - an intro image - proper spelling and grammar - appropriate cautions or safety considerations I'll give you another opportunity to make any final changes to your project before we publish it. Once you're all set to go, please republish your project and send me a quick comment letting me know that you've made some changes. I'll give it a quick final check to make sure you're on the right path, and then remove this note. Thanks for your submission and we hope to see your project published soon!
May 17, 2012. 3:43 AMnetfreak11 says:
This circuit is really good and way better. . .
One thing I want to ask is that if I want to use the same circuit for having my LED turned on for 1 second and having the same LED turned off for 1 second as well for indefinite period of time then what valued capacitor or resistor etc should I use?
Apr 24, 2012. 9:20 AMrobotmaker says:
also from the circuit you left pi4 trig un-connect shouls always pull high or it will re-trigger
Jul 26, 2011. 5:01 PMGhost915 says:
I found your schematic and it's just what I was looking for but, I found that by touching the top of the 555 timer chip it turns it on and off and controls the flashing. Is this suppose to happen?

Thanks
Apr 24, 2012. 9:15 AMrobotmaker says:
yes ,thats capacitance from your finger
Mar 31, 2011. 12:21 AMcallones says:
Tries this and it works well. what if i want it to have a lower duty cycle? what do i need to change?
Feb 22, 2011. 7:49 AMrobot1398 says:
i have made it and it works great.
i used a 100 uf capacitor
Jan 9, 2011. 2:25 AMprajwaltinkle says:
my led just lights up but doesn't flash/blink at all.....please advice.....
Nov 9, 2010. 2:04 PMtomx63 says:
my experience with this type of circuit is that the on/off intervals are equal in length. do you know how it can be accomplished to increase the off interval? say so that the LED blinks quickly once every 3 seconds.
and great job with this instructable!
Nov 15, 2010. 1:55 PMtomx63 says:
figured it out over the weekend. the combination of capacitance and resistance (excluding the LED resistor) tweaks the IC to set the desired flash intervals.
Mar 17, 2010. 1:07 AMy2knemesis says:
 hi,
    i wanted to know,what capacitor should i use to make the light blink like 60 times a minute and the reistor needed to use on a 12v supply.thanx.great work keep it up.
Jun 12, 2009. 1:23 PMLastDevil says:
Sorry for this dumb question but what will i need to make it a 12v input power?
Sep 19, 2010. 9:18 AMtacoman101 says:
Hi, I so if I use a 3V source to power a led will I need the 1k resisters?
Apr 2, 2010. 12:31 PMmax1zzz says:
 if i replace the led with a transistor could i use it to turn stuff on and off
Aug 28, 2010. 9:57 PMbrettboy01 says:
what capacitor would i need for it to blink 20 times a second because my friends halucinate when i flash lights in their eyes
Aug 23, 2010. 12:16 AMdawsonj says:
i love making these! also, its called a multivibrator
Mar 21, 2010. 2:35 PMjamilm9 says:
I just made this in 10 minute. It turned out great. Thanks 
Sep 11, 2009. 10:05 AMmatstermind says:
does it matter what voltage the capacitor is?
Oct 22, 2009. 3:41 PMmatstermind says:
"mam?
Jul 11, 2009. 12:00 AMdarkjester0130 says:
I am curious, I was wondering how to make a circuit with 4 lights, in which only one light would light up at a time and go in order from one, two, three, four, and then back to one. Also, is there a way to adjust speed on that and do the same thing with 8 or more lights?
Jun 8, 2008. 5:00 AMfkuk says:
what capasitor do i need to make it flash slower about once every 5-10 seconds
Jun 12, 2009. 2:16 PMstefannasehi says:
did he say 10uf to 1000uf or 10uf to 330uf?
Dec 27, 2008. 11:44 PMak11667 says:
hey i was doing some tinkering with this circuit learned by using a 100microfarad cap and a 10k potentiometer by upping the resistance you can modify the length and duration of the blinks you replace the 2 1k ohm with the pot and it will blink according to the pot
Mar 13, 2008. 8:04 PMarmadillozenith says:
Haven't tried it yet. But this is really useful idea, just what I wanted to find for making very simple cheap flashing light effects for sci-fi props (maybe accessories for a costume party or parade). I think I already have what I need except for 555 timers. For me, this level of Instructable is fine. Thanks!

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