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Old 08-25-2017, 07:07 PM #1
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Unhappy DOA 301/303 Laser

I just received my cheap less than advertised power 301/303 type laser pointer from Aliexpress today.

No matter what I try, can't get the thing to power on. Is there anything I can try to get it working?

I ordered this before I knew any better

Cheers!


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Old 08-25-2017, 07:11 PM #2
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Default Re: DOA 301/303 Laser

Are you sure you've got the right battery, orientation, and they're charged completely?

They have terrible contacts, so check the tailcap and connection on the module.

Otherwise, the cheap Chinese lasers like that are really hit and miss. You can dig into it and replace things if you're adventurous, but it may very well be DOA.

Sometimes, they'll send you another if you contact the seller.
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Old 08-25-2017, 07:12 PM #3
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Default Re: DOA 301/303 Laser

Quote:
Originally Posted by Msan View Post
I just received my cheap less than advertised power 301/303 type laser pointer from Aliexpress today.

No matter what I try, can't get the thing to power on. Is there anything I can try to get it working?

I ordered this before I knew any better

Cheers!

Which wavelength?

Are your batteries charged? Have you verified the voltage?

Do you have the batteries in the correct way?

Have you enabled the laser with the key switch located on the tail cap?

Do you have a multimeter at your disposal?

Have you tried anything to get it working yourself?
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Last edited by diachi; 08-25-2017 at 07:12 PM.
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Old 08-25-2017, 07:21 PM #4
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Default Re: DOA 301/303 Laser

"high power 5000mw 5w 405nm Blue Violet Purple Laser Pointer Pen laser 301 Burning Adjustable Focus burn matches with keys" was the description (link is in my first post)

I have 2 different fully charged 18650's, I tried every orientation, every key position.. nothing.
Yes I have a MM, but I'll have to wait till I get home for that, still at work.. I also left a msg with the seller, lets see what he says..
Other than that I have not tried anything else, but am willing to do whatever.. even if I break it LOL

Last edited by Msan; 08-25-2017 at 07:21 PM.
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Old 08-25-2017, 07:32 PM #5
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Default Re: DOA 301/303 Laser

Quote:
Originally Posted by Msan View Post
"high power 5000mw 5w 405nm Blue Violet Purple Laser Pointer Pen laser 301 Burning Adjustable Focus burn matches with keys" was the description (link is in my first post)

I have 2 different fully charged 18650's, I tried every orientation, every key position.. nothing.
Yes I have a MM, but I'll have to wait till I get home for that, still at work.. I also left a msg with the seller, lets see what he says..
Other than that I have not tried anything else, but am willing to do whatever.. even if I break it LOL
Are you sure it's supposed to be an 18650 and not some dual setup? Unless the laser has a boost driver, it needs more voltage.
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Old 08-25-2017, 07:35 PM #6
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Default Re: DOA 301/303 Laser

Quote:
Originally Posted by Msan View Post
"high power 5000mw 5w 405nm Blue Violet Purple Laser Pointer Pen laser 301 Burning Adjustable Focus burn matches with keys" was the description (link is in my first post)

I have 2 different fully charged 18650's, I tried every orientation, every key position.. nothing.
Yes I have a MM, but I'll have to wait till I get home for that, still at work.. I also left a msg with the seller, lets see what he says..
Other than that I have not tried anything else, but am willing to do whatever.. even if I break it LOL
Ahh, the forum theme I'm using doesn't highlight hyperlinks, didn't see that.

Also, 5W? That's a stretch, by about 50x or more.

If you tried the wrong orientation first time around it's possible that you killed the laser. These cheap Chinese lasers often don't have reverse polarity protection.

To verify further you'll need to use the multimeter.
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Last edited by diachi; 08-25-2017 at 07:36 PM.
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Old 08-25-2017, 07:38 PM #7
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Default Re: DOA 301/303 Laser

I'm pretty sure the orientation the first time was correct.. Usually the spring is the negative side..
what/where should I be measuring with the MM when I get home?
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Old 08-25-2017, 07:40 PM #8
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Default Re: DOA 301/303 Laser

Quote:
Originally Posted by Msan View Post
I'm pretty sure the orientation the first time was correct.. Usually the spring is the negative side..
what/where should I be measuring with the MM when I get home?

As in the spring inside of the battery tube towards the front of the laser?

That's more often than not the positive side for 445nm lasers. The tailcap should be the negative end.

Test for continuity (through the tailcap) and current draw (Tailcap removed, MM in current mode, one lead to the case one lead to the exposed terminal on your 18650). It's also possible that the 18650 is a little too short and isn't making contact, but I haven't encountered that with the 301/303 lasers.

By the sounds of things you inserted the battery the wrong way and killed the laser.
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405nm | Banggood LT-850 | "5mW" | Review Unit | Review WIP
445nm | Sanwu Laser Pocket Series | 400mW Metered
445nm | NDB7242E Pen Build | 60mW Metered | >>Build Thread<<
450nm | LaserPointerStore - Thor H2 | 1W(?) | Review Unit | >>Review<<
473nm | B&W Tek BWB-10-OEM | Ordered
488nm | Spectra Physics 163 Argon | ~30mW Metered
515nm | PL515 Pen Build | 50mW Metered | >>Build Thread<<
520nm | Laserlands 520 | 5mW | Review Unit | 3mW metered | >>Review<<
532nm | Gearbest 303 Pointer | 50mW Metered
532nm | Gearbest JD-850 Pointer | 30mW Metered (I think, need to re-test).
633nm | HeNe | 6mW
633nm | Spectra Physics 155 HeNe | <1mW >>Thread<<
650nm | Sanwu Laser Pocket Series | 200mW Metered
808nm | Melles Griot 532nm Lab Unit | No Crystals >10W | X2



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Last edited by diachi; 08-25-2017 at 07:42 PM.
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Old 08-27-2017, 02:11 PM #9
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Default Re: DOA 301/303 Laser

This reminds me of a time I used to sling 303's on eBay for extra laser cash. 660's, 532's, and 404's. Even with anti-static packaging, like 1 in 5 would want a refund because it was DOA. I gave them away on the LPF and nobody said they were broken. It's a funny thing because when I bought 40 or so direct from China, none of them would be defected. I have a feeling that something happens when they are shipped via airmail. Did you order express shipping by any chance?
And I don't think you killed your laser with a backwards battery. From what I remember they all have reverse diode protection even though they're really cheap.
If you had to order another one as a replacement, I highly recommend a 650 because they're pretty much all 200mW minimum, and you won't have to gamble to see if you get an 80mw+ or not
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Old 08-27-2017, 03:03 PM #10
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Default Re: DOA 301/303 Laser

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Originally Posted by AgentMcBaine View Post
This reminds me of a time I used to sling 303's on eBay for extra laser cash. 660's, 532's, and 404's. Even with anti-static packaging, like 1 in 5 would want a refund because it was DOA. I gave them away on the LPF and nobody said they were broken. It's a funny thing because when I bought 40 or so direct from China, none of them would be defected. I have a feeling that something happens when they are shipped via airmail. Did you order express shipping by any chance?
And I don't think you killed your laser with a backwards battery. From what I remember they all have reverse diode protection even though they're really cheap.
If you had to order another one as a replacement, I highly recommend a 650 because they're pretty much all 200mW minimum, and you won't have to gamble to see if you get an 80mw+ or not
AgentM, nice to see you post
I can vouch for the red 650nm as in power wise and reverse polarity protection. I remember getting the 303 650nm from you and telling you it was DOA
At the time I only had the 532's and I put the battery in case "pos" which I thought was the same, I must tried turning it on 100 times till I figured it..
Can't say for the 405's or 532's?
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Last edited by GSS; 08-27-2017 at 03:03 PM.
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Old 08-27-2017, 03:19 PM #11
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Default Re: DOA 301/303 Laser

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AgentM, nice to see you post
I can vouch for the red 650nm as in power wise and reverse polarity protection. I remember getting the 303 650nm from you and telling you it was DOA
Hey there ol friend. Ya, that was a while ago.
They're pretty much all hit/miss.
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