1. Welcome to our site! Electro Tech is an online community (with over 100,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Are these people for real?

Discussion in 'General Electronics Chat' started by Dragon Tamer, Jan 24, 2010.

  1. Dragon Tamer

    Dragon Tamer Member

    Joined:
    Oct 8, 2009
    Messages:
    847
    Likes:
    4
    Location:
    Landenberg, Pennsylvania USA
    i stumbled across this video on youtube: the video (sorry to those of you using dial-up, if you want to you can wait for this video to load or you can try this similar site: the site) what i want to know is who do these people think that they are fooling??? (if this is for real then i guess that they are fooling me :) ) i just find it a little hard to believe that you can make a burning laser just by damaging a single part in the laser pointer.
    Last edited: Jan 24, 2010
  2. vne147

    vne147 Member

    Joined:
    Jan 11, 2007
    Messages:
    875
    Likes:
    8
    Location:
    Houston, TX
    I'm not so sure about that. I like how he called his laser pointer a 5 MW laser. I think he meant 5 mW. Smells like BS,
  3. Boncuk

    Boncuk New Member

    Joined:
    Nov 10, 2007
    Messages:
    5,382
    Likes:
    87
    Location:
    Phetchabun,Thailand
    The movie shows clearly how not to do. :)

    First I wonder about the terminus technicus "5Mw". 5mW would have been the appropriate "name".

    Disassembling the laser pen the batteries should be in first place (Imagine what will happen to your eyes when twisting the laser diode cap and inadvertantly push the button with the laser pointing at you?) :confused:

    I guess its doable to increase the laser power output. I also guess he just burnt the current limiting resistor to achieve a lower (or zero) resistance.

    I furthermore guess the movie stopped at the point when the laser had reached its self-destruct point. :D

    Observing the huge light pattern I think using a better collimator lens will have the same effect - with the difference of a longer life time of the laser diode.

    Power laser diodes don't have a built in monitor diode just for fun.

    Boncuk
  4. Sceadwian

    Sceadwian Banned

    Joined:
    Oct 27, 2006
    Messages:
    14,047
    Likes:
    140
    Location:
    Rochester, US
    Funny. This isn't the first thread that's linked that same video :) it's been around the net a few times, or at least one identical to it. I agree with pretty much everything Boncuk said. The dial he adjusted with the screwdriver was part of the feedback control for the laser although I'm not entirely sure what component he 'disabled' with the soldering iron, wouldn't a resistor go to a higher value not a lower one when overheated? Not really sure. It will definitely increase power, and definitely decrease lifespan if not outright destroy the laser module if done incorrectly. I'm also a little skeptical of how fast the match went up after the adjustment, if it were that high powered the camera lens should have been nearly over powered with the reflected light coming from it. I like the different color of the green lasers and the super bright ones are nifty because they can be seen in air in a dark room or at night but I never quiet understood the fascination with igniting matches. Considering how far down in cost green laser modules have come if you really wanted to play around with one I'd say go for it.
    Last edited: Jan 24, 2010
  5. Vizier87

    Vizier87 Active Member

    Joined:
    May 12, 2009
    Messages:
    1,462
    Likes:
    11
    Location:
    Johor Bahru, Malaysia
    I recalled mugumbo with his classic quote "all you people replying to this thread are idiots". If he comes here again let's bash him!
  6. Sceadwian

    Sceadwian Banned

    Joined:
    Oct 27, 2006
    Messages:
    14,047
    Likes:
    140
    Location:
    Rochester, US

    What? Why Vizier?
  7. Boncuk

    Boncuk New Member

    Joined:
    Nov 10, 2007
    Messages:
    5,382
    Likes:
    87
    Location:
    Phetchabun,Thailand
    Hi Sceadwian,

    as with most things in life you'll have two choices. :)

    Burning a metal film resistor it might cause a dead short or be a perfect isolator.

    Burning too fast and at high temperature makes it a way it can't be used to increase power of the laser diode, since the metal film will evaporate turning it into the latter of the two possibilities. :D

    Metal film resistors have a negative temperature coefficient other than carbon film resistors.

    Applying the right temperature and amount of heat will decrease its value forever. (In circuit resistor trimming, as used by a japanese electronics component manufacturer)

    I'll try to get a datasheet of those trimmable resistors, just can't remember the company name presently.

    Regards

    Boncuk
  8. Sceadwian

    Sceadwian Banned

    Joined:
    Oct 27, 2006
    Messages:
    14,047
    Likes:
    140
    Location:
    Rochester, US
    Thermally trimming resistors, hmm nifty =)
  9. Mr RB

    Mr RB New Member

    Joined:
    Jul 22, 2008
    Messages:
    4,717
    Likes:
    189
    Location:
    Out there
    You can just remove the circuit from the laser diode and drive it with any DC power level you like, no need for silly circuitry mods.

    But just like a LED there is a very limited range of power you can get out of one before it just burns out.
  10. Vizier87

    Vizier87 Active Member

    Joined:
    May 12, 2009
    Messages:
    1,462
    Likes:
    11
    Location:
    Johor Bahru, Malaysia
    Last edited: Jan 25, 2010
  11. audioguru

    audioguru Well-Known Member Most Helpful Member

    Joined:
    Mar 16, 2004
    Messages:
    29,525
    Likes:
    699
    Location:
    Canada, of course!
    The video is BS.
    The "laser" pointer has a beam like an ordinary green LED, not like a very bright and thin laser beam.
    I don't think two AAA alkaline cells can produce enough heat in anything to light a match.

Share This Page