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LFTT (LED Flashie Throwie Thingie)

LFTT (LED Flashie Throwie Thingie)
You may already know the LED throwies

The LED Throwies are very cool, however they could be a little more attention getting with just 2 extra components.

This Instructable will show you how to make a flashing LED Throwie.


 
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Step 1Parts list

Parts list
To make one LED flashie you'll need:

a 10mm LED (I recommend, that you use a diffuse LED. I live in Denmark and the diffuse LEDs aren't available here, so I just used a waterclear type)

a CR2032 lithium coincell battery.

a Neodymium (NdFeB) disc magnet.

a LM3909 LED Flasher circuit

an Electrolytic capacitor (the bigger the capacitor is, the slower the LED flashes. I figured out, that a 100µF works fine. It will flash the LED at approx. 2.5Hz, while a 220µF will flash it with 1Hz.
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52 comments
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Apr 30, 2009. 6:24 AMzs1apb says:
Hi there. LM3909 IC's have been obsolete for at least the last 10 years :-(( Anyone know of a cheap source for these? Regards. Tony
May 20, 2011. 9:52 AMyukthi says:
yes its true !!!
Feb 15, 2010. 12:57 AMzs1apb says:
Hi there. Only picked up your reply now :-(  Apologies!! Would appreciate you finding out how many LM3909 IC's your local supplier has and at what cost.
These chips have been unobtainable her in South Africa for the last 7 years :-(((  Thanks and regards.
Mar 25, 2011. 10:48 PMrobot1398 says:
i agree with catman0321
here is a instructable
http://www.instructables.com/id/how-to-defuse-an-LED/
Oct 8, 2010. 4:26 PMcatman0321 says:
you can just sand the led down with sandpaper
Jul 20, 2009. 11:30 PMagis68 says:
for anyone who needs forgotten LM3909!!! I found in a store here in Athens some boxes containing thousands of this IC, so anyone who wants some of them are available!!! costs 0,80 each
May 9, 2010. 8:36 AMzs1apb says:
Hi  there. Are these still available? If so what is the cost and how much to post to South Africa? Thanks and regards. Tony
May 12, 2010. 11:41 AMagis68 says:
 I have to check  it first
Apr 6, 2010. 3:39 AMporryman says:
How much time should the batterie be alive??? I've made the same circuit and the first batterie ruined out in 1 week. I used a 100 µf / 25v capacitor and a ordinary red led diode.
I've read the lm3909 datasheet and with a 1,5 v AA batterie it should be working for at least 6 month.
What could be wrong??

Thank you very much in advance
Nov 13, 2009. 6:10 PM3unchi says:
Hehehe video sounds like Pentax :D
Oct 16, 2009. 10:14 AMSpeeddemonrs says:
Wow, how much radiation does that thing put out?!?!? In the video, it sounds like the geiger counter is going CrAzY!! lol!  Neat idea!
Sep 29, 2009. 6:52 PMalbylovesscience says:
more like led sezure throwie just kidding
May 27, 2009. 12:47 PMwillymakesstuff says:
WHAT PINS!!!!!!!!!
May 17, 2009. 5:57 PMacmefixer says:
Pro: having an all-in-one flasher chip makes this project much, much easier, compared to using discrete components. Con: The LM3909 is an obsolete chip, no longer manufactured, thus It is not available from most suppliers. When the very small "New, Old Stock" supply that is left is used up, it will be impossible to obtain more. You had better start retrieving your old throwies and reuse them. Maybe a CMOS 555 chip or a flashing LED might be the answer. Good luck.
May 11, 2009. 6:10 AMbuteomont says:
You are only 14 years old, and can make better instructables than many adults. Keep it up, you'll make a lot of money one day!
Jun 23, 2008. 7:00 AMsamphantom says:
Hello there This is interesting but I do not know if you know, but there are in the market built in flashing LED and the cost of those are very cheap, the bad thing is I believe they comes in red and yellow but for the instance u can add this flashing leds in series to another color LED you want. You can find them in Digikey online. But is good though.
Dec 30, 2008. 2:35 PMdaniel! says:
You can diffuse an led by sanding it with sand paper. My mom is from Denmark so I visit there a lot and speak danish fluently.
Nov 4, 2008. 4:10 PMCoodude26 says:
Can't you but LEDS with blinking modules built-in?
Nov 4, 2008. 4:11 PMCoodude26 says:
oh sorry nm
Oct 22, 2008. 4:43 PMalex-sharetskiy says:
blinking LED?
Sep 10, 2008. 9:35 AMCurious seb says:
What componnent you use to make it and where are you buy it. how long is working with one battery.
Jun 24, 2008. 6:53 AMsamphantom says:
Hello my friend. Keep the good track line with your invents, the less I want to do is to take you out of this precious career. Some times is difficult to find components in other areas but still you can order this items sometimes for free in some online sites (e.g. www.texasinstruments.com). But do not worries it will came the day that you can buy your own items. I did not looking for 10mm flashing diffused leds but I'm sure there will be. Anyways thank you for your comments and if there is anything that is on my hands to help you let me know.
Jun 22, 2008. 10:24 AMdarkbain says:
Ha, indestructible...how did that happen
Jun 14, 2008. 5:10 AMdarkbain says:
I like this indestructible, it's well illustrated. Blinker circuits (especially for throwies) never get old. Thanks for posting.
Jun 20, 2008. 1:18 AMMattrox says:
dontcha mEAN instructable
May 26, 2008. 3:12 PMassasin090 says:
whats a throwie?
May 24, 2008. 5:19 PMsurviverman says:
(removed by author or community request)
May 12, 2008. 7:36 PMtherian says:
using chip for such task is overdue, 2 transistor audio oscillator will do the job and parts can be salvage from anything
May 13, 2008. 5:47 PMtherian says:
maybe I just too cheep but I love to salvage parts , the feeling of making something from "nothing "
1-40 of 52next »

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Author:Artificial Intelligence
Hi all, I'm a college student in the copenhagen technical college. I'm currently working with 3D printers and I'm building my own RepRap.