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ArcticMyst Security by Avery

Need Help With 200mw Green Dealextreme Module

Joined
Oct 30, 2015
Messages
64
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8
Hi guys i'm new member of LPF, but I've been reading threads from here for a long time. Anyways im having a problem with my dealextreme 200mw green laser module (200mW 532nm Green Laser Module (3V 11.9mm) - Free Shipping - DealExtreme). When i received the module i decided to replace the black wire with a spring, so i soldered a spring from a 5mw module on to the 200mw module and it eorked great. sadly while i was making sure the button lined up in the host i was using (from a dealextreme 5mw laser) the spring broke off. I thought it ws no big deal because i coud just solder on a new spring (i didnt want to use the one i had used befor because during the reassebly process i had bent it pretty badly, so used a spring from a pen instead. i soldered that on and tried the module out again and this time the module didnt work in the host. I noticed when i pulled out the module that the spring on the module and the batteries had become very hot as the spring had shrunken like a hair does when its burnt. I believe that that was the result of a short circuit between a little bit of excess solder that was stuck on the back left tab on the button (if youre looking at it with the brass part in front) and the inside of the host. But me not knowing what a short circuit was at the time thought the spring was to blame for the module not working, as it was not a spring that was intended to conduct electricity. So i desoldered that spring and soldered on a spring from a dollar store flashlight. i put the module back in the host, making sure the spring didn't touch the inside of the host by using the foam ring that was on the old 5mw laser spring i used first. This time the laser still would not lase.:cryyy: And now i have decided to cut my losses and ask for help. after looking at the board my only explanations are that i burned the pcb (it kinda looks like excess flux though) or that the diode overheated during the short.

If any one could help me figure out what is wrong with the module that would be great.

Here are some pics of the pcb:

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Joined
Sep 12, 2007
Messages
9,399
Points
113
Try powering it while not assembled. Does it draw current with a button press?
 
Joined
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Messages
9,399
Points
113
A digital multimeter (DMM for short) is a requirement for anyone doing electronics work. They're $10 online - get one and learn how to use it. Google can help.
 

Pman

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Touch the negative to the spring and the Positive right onto the brass/heat-sink and push the button.
 

Pman

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Well your volts are a bit low but yes, just hold the negative to where the spring connection is and the Positive to the laser brass anywhere and push the button down and see if you get an output.
That's the basic simple way to test. As Cyp mentioned, having even a cheapo multimeter is a must have to further troubleshoot if you still get no output.
Any reason why you can't just use 2 new batteries? My guess is 5hat you are very young and saved up for awhile to buy this. It's VERY doubtful that laser is anywhere near 200mW. It's far more likely it is between 50-just over 100mW which is sill easily seen in semi dark or with some light inside. You can get modules like that for about $6 at Fasttech with free shipping. They are the 3V and 5V ones rated at 5mw (or <5mW). They are WAY overspec.
 
Joined
Oct 30, 2015
Messages
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Points
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Well your volts are a bit low but yes, just hold the negative to where the spring connection is and the Positive to the laser brass anywhere and push the button down and see if you get an output.
That's the basic simple way to test. As Cyp mentioned, having even a cheapo multimeter is a must have to further troubleshoot if you still get no output.
Any reason why you can't just use 2 new batteries? My guess is 5hat you are very young and saved up for awhile to buy this. It's VERY doubtful that laser is anywhere near 200mW. It's far more likely it is between 50-just over 100mW which is sill easily seen in semi dark or with some light inside. You can get modules like that for about $6 at Fasttech with free shipping. They are the 3V and 5V ones rated at 5mw (or <5mW). They are WAY overspec.


I have a digital multimeter and I now know how to use it. I appologize for my ignorance, I knew that it wasn't going to be 200mw but I bought it anyways because I thought it was a good deal. I understand that I could get another module with the same specs for quite cheap however I thought it would be interesting to try and troubleshoot the one I already have and maybe learn something along the way :)
 

Pman

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Did you try the test? Only takes a moment.
 
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Did you try the test? Only takes a moment.

Yes I just did, it appears to be drawing about 60mA of current when the button is pressed. I tried touching the two probes to the spring and the brass while connected to power but I was getting a reading even if the button wasn't pressed. Based on the video I saw the current runs through the multimeter, so I assumed that I was just shorting the two batteries. I measured the current by attaching the positive lead (from batteries) to the positive probe of the multimeter, and then touching the negative probe to the brass on the module. It then read 0 without the button pressed, and read around 60mA with it pressed,
 
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thank you guys for all of your help:thanks:, but ive decided to cut my losses and just get a new module:cryyy:
 

GSS

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What happened when you just used the battery test like Pman said?
 

Pman

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Try not to triple post. Just edit the post instead.
60mA is way too low. With the fasttech modules I set the pot for 430mA for max output. I've seen from 50 to 141mW setting that way. It's just luck of the draw. Are you sure it wasn't 600mA which is way too high unless you actually are going to be around 200mW. If you haven't sent it back you should adjust the pot to between 300-400mW and see if you get a strong beam.
Also, you should not use a conductive screwdriver to set it with power applied. You can buy ceramic ones from fasttech. Easy to short the switch otherwise.
Unfortunately my guess is that you messed with it too much and it's dead.
 
Joined
Oct 30, 2015
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i appreciate your guys' help but while i was testing the module it rolled off of my work bench and one of the diode pins broke right off the diode itself so i think this one is a goner, but i definitely got my money's worth just from messing around with it. i'll just get another one and learn from my mistakes, no big deal.
¯\_(ツ)_/¯
 




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