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how to wire a 555 IC timer

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Deleted member 16589

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I bought a 555 timer from radio shack but do not know how to wire it
I need to pulse a laser.
I need to be able to turn 2 potentiometers to adjust the speed and length of the pulse
can any one ether tell me how to wire it or have a simple diagram on how to wire the circuit
 

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Deleted member 16589

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I just follows 5 you tube videos and none of them worked I dont get it does the chip need to be set ????????????????
 
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^did you check the link I gave you? It's all there.. everything you need to know about 555 timers. Check post #2.
 

lasersbee

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I just follows 5 you tube videos and none of them worked I dont get it does the chip need to be set ????????????????
Check out EF's post #2 and stop relying on You Tube...
I don't believe half the crap that is on there...

You can google the LM555 Data Sheet for even more techical
information...:cool:

@EF... I guess you can lead a horse... Bla.. Bla.. Bla...


Jerry
 

stitch

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I feel your pain. The 555 timer is how I started out and trust me, it was crazy trying to find info on its operation, but Google is most definitely a valuable resource (as is the library!). Anyways, I'll give you a quick rundown...
Since all you need is a pulsed output, I'll show you what you may have already learned - the astable mode.
http://www.box.net/shared/ahohc5moxa
Above is a layout on the right, and the schematic on the left. Since you bought it from Radio Shack, it should have the pin layout on the box (got mine from radio shack too, lol)
Anyways, the resistors and capacitor are the things that pretty much what set the Time High and Time Low. That basically means, the on/off time. Now, I'm not sure what the specs are for your project/application, so here is a formula you can use to calculate the frequency of pulses.
TimeHigh(on)=0.693C1(R1+R2)
TimeLow(off)=0.693C1R2
Frequency(in Hz)=1/(0.693C1(R1+2R2))
Here are some tips, though, so your math comes out right...in these equations, you want to put the resistors (R) in ohms, and the capacitor (C) in farads. Example, if you're using two 470 ohm resistors and a 4.7uF capacitor, it would be like this...
Frequency=1/(0.693*.0000047(470+940))=217.75Hz
Resistors are easy, but capacitors, well, they end up having a lot of zeros. You will see most capacitors with a value of something uF. 1 farad is 1,000,000uF. A lot of zeros.
Anyways, I hope this helped you a little bit. The math can get a little messy but in the end, the 555 timer is a lot of fun. Good luck!
 

stitch

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Oh yea, I forgot. You wanted to add pots in the equation, too. One pot should do the trick.
http://www.box.net/shared/ddq51co4bj

I know you said two (one for speed, one for length) but if you think about it, if you lengthen the time between pulses, you're basically changing the speed lol
 
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ok fine ill tell you and just for the record he is not the first to do this he saw mine and wants to imitate it like in my video here------> http://laserpointerforums.com/f45/three-mirror-green-laser-spirograph-49675.html for an easy way to do it with no understanding of wave forms, 6 to 2, 1 to neg, 4 and 8 to positive just for starters. wire a resistor from positive to one lead of your potentiometer then the other leg of a potentiometer to the positive side of you capacitor then the neg leg of the cap to ground. then a straight connection from 2 to the positive junction of the potentiometer and positive leg of the cap. and your output will be 3. i hope you can atleast work with that information because i was hoping you could without.

-dakota
 
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idk if this counts as spamming but if any of you are interested in buying a laser driver driver lol im building a better one for more effects and if you want a full 3 or 4 mirror set up that could be possible also

-Dakota
 

stitch

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Xplorer, I checked out your link (curious) and it was pretty awesome. It's pretty cool to find out that there are still things to learn!
 




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