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ArcticMyst Security by Avery

halfway fried?

budule

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i have a green cheepie that i shortened for a vortex machine, it was working fine off 2 aa batterys but i wanted to use a wal wart...now it only seams to work at half or less power ...can it be "halfway" fried? just toss it or is there hope?
 





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if it's still dim when run back on two AA batteries then yea it's probably fried - but don't toss it, someone is likely to buy it for a few bucks
 

budule

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damn it!!! should i have used a "regulated supply" instead of a transformer?
 
B

Burningbeams

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Also make sure that the transformer can output enough mA to run the laser.. depending on the greenie, you may find that it draws 700mA from the AA's :eek:

If the laser still functions properly on the AA batteries, somehow place your multimeter leads in series between the batts and the driver, and measure the current draw. Then, measure the voltage output from your transformer and make sure it isn't over 4 volts or so. You may also be able to set your multimieter again to measure current, and measure the current the transformer puts out-- be careful-- make sure your mutimieter can handle the current.....
 

budule

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i was trying to run the fan and laser from the same source, i did find a switchable (3,5,7,& 12volt) 1 amp regulated supply so i'll try that i guess
 

diachi

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try it at 3V first , the fan would probably drain a fair bit of current, depending on the votlage
 

IgorT

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It is possible, that just the regulator is damaged. It is designed to operate from a very low voltage - what voltage did you feed it anyway?

If the wallwart you used has a 3V setting, and is unregulated, it does like 5V (depending on it's current rating) at this setting, and this voltage then sags with current draw.


But what laser is it anyway? Some have a non working regulation, and there the diode would get fried, but if it's still doing green, i find that unlikelly (even tho i had a pump diode that lost 1/3 of it's power after using a 3.6V instead of 3V battery - but the green dropped more than half, so yeah, it can be halfway fried). The crystals can suffer damage too tho.


If it's just the driver, you could make a new one, if you know what the old one was drawing from the batteries. If you do, you can also check what is wrong with it this way - measure the current from two batteries. If it's the same as before, it's the diode.
 

budule

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i tried it with the battery and its still dim....wal wart was 5volts with no load then dropped to 2.67 with fan and laser...its just a cheap greenie (dealtime hong kong)...i was using it with 2 aa batterys to run the laser and the fan (very small 5 volt fan) it worked fine but i needed it to work off 110 so i could remote control it..
 

budule

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maybe i should ask first, (if i would have done that first i wouldnt have a fried laser) will aforementioned power supply (switchable 3. 5 .9 & 12 volt regulated 1 amp) have any problems running the laser and the small fan?
 

budule

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not sure , it was a cheapie dealtime hong kong express ....seamed to work fine (right up until i fried it that is)
 

IgorT

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Do you have a DMM? If you do, please measure the current consumption from the batteries. Use the highest current range, and put the DMM between the battery and the laser, so the current can flow through it. You also need to switch the probes to a different socket..

If you measure the current, that could help diagnose the problem.


Otherwise, i'm guessing you're taling about DealExtreme. Do you at least remember the price? And what does the label on it say?
 

IgorT

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budule said:
maybe i should ask first, (if i would have done that first i wouldnt have a fried laser) will aforementioned power supply (switchable 3. 5 .9 & 12 volt regulated 1 amp) have any problems running the laser and the small fan?

The power supply wouldn't have a problem. It also won't sag, since it's regulated.

But the laser would have a problem. You shouldn't be running the fan and the laser off the same voltage. The fan needs 5V and the laser needs 3V.


So the least you would have to do is put some diodes in series with the laser, to drop the voltage to around 3V. Even better would be, if you made a driver for the laser. Then, both the fan and the driver could run off the same voltage.

Many of these lasers have drivers, that don't do much more, than a resistor would. So if you increase the voltage, you increase the current. With a proper driver, this wouldn't happen, the current would stay the same, but the driver would heat up more.

So if it's an unregulated laser, you fried the diode. If it's regulated, you could have fried the driver. That's why you should measure the current it is drawing from the battery - to see what happened. If it's drawing the usual amount of current, the diode is dead. Unfortunatelly, we don't know what the usual amount of current is, as you should have measured it while the laser was still fine. But if you read the power on the label and measure the current, it would give an idea, if it's right or not.
 

budule

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the fan runs fine on 3volts...i had both hooked up to a AA battery holder with a switch and used it on and off all nite....(had a outdoor party and broke it out after everybody had a few....just flat out fried some peoples minds... the fog and wind was just right...couldnt belive myself how BIG this thing got)
im fairly stupid on the electronics side (well ,all the way stupid)
power output <5mW
wavelength 532nm
i cut it in half and soldered my own leads and taped the button down
this is the fan
http://www.allelectronics.com/make-a-store/item/CF-269/5VDC-45MM-COOLING-FAN/-/1.html

it still works a little, 3 or 4 feet of weak vortex....i guess i can still use it for halloween, maybe in the witches culdren or coming out of a pumpkin or something.... ive got another one i paid about 50 bucks foe that i hate to cut but I MUST HAVE THE VORTEX!!!
 

IgorT

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If it's the black rubber coated DX model, then you don't really have to cut it to power it from the outside. Does it unscrew in the middle or at the tailcap, for the batteries?

Anyway, if you do it right with the $50 one, it won't die. Just measure the current from two fresh new batteries FIRST, and write it down. Then make sure it doesn't go higher than that. If you set the supply to 3V, it shouldn't kill the laser tho.
 




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