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ArcticMyst Security by Avery

hi im new

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hi i was wondering if someone could help me out with some probloms i have with my science fair project
 





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thx lol... dose anyone know what a 100 ohm pot does... like is it really nessasary?
 
S

SenKat

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mclovin said:
thx lol... dose anyone know what a 100 ohm pot does... like is it really nessasary?

Necessary for WHAT ?

If you are looking for assistance with something, SPIT IT OUT - SPEAK UP C'mon people...is it that hard to say what the hell you are asking ? If you ask Mrs. Pott, YES....a 100 Ohm Pott is needed....she would be horribly lonely without him at home. GAH !!!!!!!!!!!!!!!!!!!
 
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McL --

Are you using it as a potentiometer or a rehostat ?? How many amps ??

Remember -- Ohms law IS the law.....

Mike
 

Things

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welcome tot he forum! ;) If you are building DDL's circuit, then yes a 100ohm pot is needed, or a known value resistor.
 
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im making the dvd burner laser and i saw a video on youtube and the guy said i need a 100 ohm pot but the other people didnt have any... im only 14 and im new at this... i need a good mark on my science fair to boost my mark... can someone just post the stuff i need..?? i have a 3-AAA holder and a switch so far
 
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Do you have a laser diode? Or a DVD burner you can get one from that no one will miss? :)

The 100 ohm pot helps to adjust the current (the volume of electricity flowing) to the diode.

You will need a few other parts as well, and you can get them mostly at Radio Shack if there's one near you. 1N4001 diode, 47uF ("micro-farad") capacitor, LM317T voltage regulator chip.

You'd also do well to NOT go strictly by the video, but look at the how-to on the site here:

http://www.laserpointerforums.com/forums/YaBB.pl?num=1185701612

You'll see a step by step writeup there.

Also, if you're new to this, BE VERY CAREFUL! These diodes can put out a LOT of light and can cause you and people around you some real problems if your foolish. Besides, it makes it all that much more fun if you have to hand out laser safety goggles to people and tell them to "Stand Back!" before you turn the thing on!

Remember that if this is for a science project, then they're not just going to want to see a pile of parts that can burn things - they're going to want to know that YOU KNOW HOW the diode burns things. What's so different about laser, or "coherent" light that it can burn things powered only by a few AAA batteries? If you can provide an effective writeup on the how and why of lasers, it'll boost your grade a lot too.

Lasers as a hobby can be fun. If you decide to follow up on it and get into a laser-electrooptics program in school, it can be an exciting and fun career - and lasers and light-logic is what's coming up. 10 years from now, we'll have computers no longer based on electronic circuits with wires and foil PC boards, but all fiber and light, with lasers driving the whole thing. Computers will be 1000x or more faster than they are now, with storage capacity measured in quads (one quad = 1000 terabytes, or 1 million gigabytes). If you're well skilled in lasers, you'll be at the forefront of this movement and well suited for a long career.

So head on over to the tutorial at http://www.laserpointerforums.com/forums/YaBB.pl?num=1185701612 and have a great time.

Also - there's a LOT of very helpful and knowledgable folks here, but we all expect you to read the material first and come with an "informed question" - meaning that you know exactly what info you need and you've stated it well because you've read as much as you can from the other forum posts. That way you make it easier for US to give YOU exactly what you really need, without having to teach you the basics that are up here already, free for the taking.

Have fun, be safe, and welcome to the forum.

D
 

chimo

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Since this is a school project, it is intended for learning.

Rather than forum members spoon feeding you the answers, I would suggest you start researching in the EXPERIMENTS & MODIFICATIONS sub forum and click on ***THREADS OF INTEREST***. All the infirmation on creating drivers you are looking for can be found there. Good luck on your project.

mclovin said:
im making the dvd burner laser and i saw a video on youtube and the guy said i need a 100 ohm pot but the other people didnt have any... im only 14 and im new at this... i need a good mark on my science fair to boost my mark... can someone just post the stuff i need..?? i have a 3-AAA holder and a switch so far
 
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i found cheap 100 ohm pots on the fourm and i think im going to buy a sony 16x diode from stonetek electronics.. and ill read those links right now... thanks for the help
 
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Yeah senkats diodes are good, can handle pretty high temps to, if you want it to live long dont give it more than 250ma

I wish my school had science fairs.. my other one used to and i got first and second place alot lol, one time i just put some cornstarch and oil in the microvave and made biodegradable plastic and got 1rst place :eek:


....lazer... ;D ;D ;D
 
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Ideally, you should figure out what a 100ohm pot is and what it does for the circuit. If you're going to build that circuit and not blow your diode, you really should learn what every part in there is, what it does, why its needed, and how to change it if you want.

Especially if you're doing this for science fair. Not sure if this is just some school assignment, or if you're looking to be competitive, but I've been to state ISEF a couple of times and you'll honestly be screwed if this is all the research you've put into it.

Making a burning laser is a nice ideal, but its a DIY job for hobbyists who understand what they're doing. If you just follow a guide and put stuff together, you may get lucky, but if you actually understand how everything works, it'll make it a lot easier for you, and let you how to customize your own design.

For starters, I'd suggest reading up on electronics and the basics of LM317-based circuits.
 
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yeah.. ive been doing some reserch.. im going to call mt grandpa... he knows alot about this stuff... he used to b a computer prograer
 
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ok today i went to radio shack and i got a silicone diode, resistors, a switch 2-AAA holder, wire.... the only bad part is i got a pot but all they had was5k ohm... will that do the job??... i cant get a hold og my grandpaw because he is in the hospital in wakefeild quebec canada... so can someone help me.. all i need to know is what i need exactally to build this thing
 
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a 2aaa holder want work, the lm317 needs at least 6v even 4aa's will die fast, id buy a 6v or 7.2v recharable ni-mh racing pack (like used for remote control cars) a 5k pot wont work its to much resistance, cant really control anythin with it one fraction of a turn on it would change the ma going to it by alot, no real control at all.

...lazer... ;D ;D ;D
 
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ok well can you tell me where to get a cheap 100 ohm pot??... and do you know how much heat a diode fromstonetek electronics puts outt... im thinking of ordering one tonight? thanks alott
 




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