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My project ( so far )

diachi

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Well guys ( and gals ) this is my first project so far, I've only worked on it for today, but alread I have all the switches mounted, one of the batteries mounted the LEDs mounted and the fan mounted, so far no laser to put in it, should have that in a few weeks .

I have only hit one problem so far and that is that the warning LED's dont seem to work with any batteries I have so I'll get some new batteries and try connecting them up.

View of the project box and switches / LED's



Close up of switches and LED's



Inside the Box



Under the lid




well thats my project so far, will hopefully get the LEDs working tomorrow, then I just need to wait for the laser, will post pictures when its all working.

Diachi
 

FireMyLaser

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Key-switch = nice!
It looks like an exiting project, seems like you mean serious business by using a fan. But what is it? A red laser? I'm scratching my head here. ;D

Anyways, about the LEDs, did you use any resistors? Or did you just connect them directly to battery?
If so, that could very well explain why they don't work with anything.


You'll probably fix it, good luck with your build m8! :)
 

Switch

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Well by the position of the fan I don't see it cooling anything.Is it a spyrograph? Or am I not getting the right picture with the fan? Is is a blu-ray or an open can project? :-/
 

PharmD4

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Good luck with your build Diachi, reminds me that I have to get started on a build. I would like to start with a liquid sky effect if possible if I can find the time and parts to make it!!

PharmD4
 

kevj2

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hi i helped him with this progect and it was him that got me so into lasers no he is made me want one so i bought my first laser i bought a Romisen L-A030 30mW Mini Green Laser the same as him
 

diachi

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Because he thinks its not that ugly, and he likes the brightness.

And so everybody knows its going to be a green, the fan is there to help cool the driver for the laser which heats up ALOT, I also bought some mini heatsinks for the chips regulators and resistors. ( there are holes in the bottom of the box so air can flow )

And thanks FireMyLaser that would sort my problem , never even thought of that, even though I knew that.

I'll need to do some V=IR ( Ohms Law ) to work out what resistance I need.

thanks,


Diachi
 

diachi

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ok...

V=IR
R=V/I
R=1.5/0.026
R=57.7 Ohms :D

Better get to work measuring the resistances of my resistors.

thanks again FireMyLaser

Diachi
 

diachi

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IM going to need 7 resistors  ;D

Might go into town and buy some 55 Ohm Resistors .

Pic of my 7 resistors joined together :

Never worked ;D
 

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FireMyLaser

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A green laser, huh? How many volts do use for this thing?


Just to give a full example on how to do:

R=U/I

Supply voltage - LED voltage / the LED current (in amps)
6V - 2V = 4V / 0.02A = 200 ohms
Or you can just google for "LED calculator"


But you can also do it in this way:

6V - 2V = 4V / 0.01A = 400 ohms


Now is the LED set to halve of the current, but it's still bright enough for an indicator. If you use super bright LEDs and set them to an even lower current, they'll pretty much take no energy at all. ;D


Never worked ;D
Did you replace the completely trashed LEDs? And for God's sake check the polarity. ::)
 

diachi

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I checked the polarity, the LEDS still work, got 52 ohm resistors, you said I needed 400 Ohm ?

diachi
 

FireMyLaser

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No it was just an example, I don't know how many volts you use. I guessed 6V.

If you use 6V, then any resistor between 200-1000 ohms will work just fine. I generally use a 1000 ohm (1kohm) resistor for indicators because they let a low current flow and still be bright enough (I also like to use bright LEDs). Plus the system voltage doesn't mean much. It works good at 5V up to 16v. After the will the resistor make too much heat and be inefficient.

Ones again good luck!
 

kevj2

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Well I'm using 1.5 V and I'm not using any resistor, it does work, granted not very bright, one of the LEDs has a bad connection at the switch and needs a little work done to it, other than that its fine.

Diachi
 

FireMyLaser

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kevj2 said:
Well I'm using 1.5 V and I'm not using any resistor, it does work, granted not very bright, one of the LEDs has a bad connection at the switch and needs a little work done to it, other than that its fine.

Diachi
WTF! Who are you "kevj2"?!

BTW, LEDs need more that 1.5 volts to work properly.
 

kevj2

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I'm the Co-builder lol, me and diachi are sitting beside each other just now :D :p

do you think 3v would do ?

kev
 

FireMyLaser

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Some normal voltages for LEDs:

IR = 1.4V
Red, orange, yellow, yellow-green (standard green) = 2v
Green, blue, white, pink, violet = 3.4V-3.7V

So for a red LED you'll need at least 2V, but ideally 3V and a resistor (>50 ohms).'


Why don't you use the same battery as the laser?
 




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