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07202010, 03:50 AM  #33  
 
Class 3B Laser Join Date: Dec 2007 Location: Ottawa, Kansas
Posts: 2,524
Rep Power: 121 
DC batteries can spike, but with regular use I don't think they would as much. On a small sidenote, where are you finding these 5A and 9A drivers? I have a custom one off host for my phlat red LED that I'm going to throw together, but I need a driver.  
07202010, 03:57 AM  #34  
 
Class 3B Laser Join Date: Mar 2010 Location: Jackson, TN
Posts: 3,234
Rep Power: 173  It's not a voltage spike. That's not going to happen with a battery. Excessive inrush current would be the problem.
 
07202010, 04:21 AM  #35  
 
Class 1M Laser Join Date: May 2008 Location: Ohio, USA
Posts: 101
Rep Power: 11  I may just give it a try tomorrow. I've got three 445nm diodes, and even if I ruin one they're only going to get cheaper to replace, I guess.
 
07202010, 04:25 AM  #36  
 
Class 3B Laser Join Date: Mar 2010 Location: Jackson, TN
Posts: 3,234
Rep Power: 173 
Not by much until projector prices come down. At the cheapest i've seen a130's, the per diode cost has been $31.something. (don't remember the projector price anymore) Plus something for the time and trouble of extracting them, $35 is the cheapest they'll be.
 
07202010, 04:34 AM  #37  
 
Class 1M Laser Join Date: May 2008 Location: Ohio, USA
Posts: 101
Rep Power: 11  Yeah, $35 is a pretty awesome price. They were $50 when I got these and I had to wait on a group buy.
 
07202010, 04:40 AM  #38  
 
Class 3B Laser Join Date: Mar 2010 Location: Jackson, TN
Posts: 3,234
Rep Power: 173 
I've seen them for $35 in the BST section. Not sure if those threads are still open and taking orders though.
 
07202010, 04:49 AM  #39  
 
Class 1M Laser Join Date: Jun 2010
Posts: 164
Rep Power: 8 
I may regret it but I'll try it considering that your battery gives 600ma and people have run their diodes at 1.52A. I have a 2 ohm and a 20 ohm resistor that I'll use with it. That just leaves heat sinking and collimating.
__________________ Notes to self: If you're bicycling backwards up a hill at a downwards speed of 37 miles per hour and it begins raining maple syrup how many pancakes does it take to shingle a dog house? Answer: onionbanana juice! The formula for finding the answer to any impossible question is onionbanana juice divided by the square root of infinity. Note safety features > If you don't understand the above ask jack sparrow.  
07202010, 05:13 AM  #40  
 
Class 1M Laser Join Date: May 2008 Location: Ohio, USA
Posts: 101
Rep Power: 11 
Well, I just joined the Direct Drive Club, and so far it's good.
 
07202010, 05:25 AM  #41  
 
Class 3B Laser Join Date: Mar 2010 Location: Jackson, TN
Posts: 3,234
Rep Power: 173   
07202010, 05:29 AM  #42  
 
Class 3B Laser Join Date: Dec 2007 Location: Ottawa, Kansas
Posts: 2,524
Rep Power: 121   
07202010, 09:08 PM  #43  
 
Class 1M Laser Join Date: Jun 2010
Posts: 164
Rep Power: 8 
Something's not right because with a 2 ohm resistor in place my diode pulls nearly 780ma of current but it's not as bright as I expected. I suspect that the voltage may be lower than it should be. I know that a 300mw IR diode will quickly burn holes in electrical tape at extremely close range even when uncollimated but with the same resistor and an extra AA battery this one doesn't give enough light to heat anything. Meh I'll figure it out given enough time.
__________________ Notes to self: If you're bicycling backwards up a hill at a downwards speed of 37 miles per hour and it begins raining maple syrup how many pancakes does it take to shingle a dog house? Answer: onionbanana juice! The formula for finding the answer to any impossible question is onionbanana juice divided by the square root of infinity. Note safety features > If you don't understand the above ask jack sparrow.  
07202010, 09:19 PM  #44  
 
Class 2M Laser Join Date: Jan 2008 Location: Maine, US
Posts: 673
Rep Power: 31  Quote:
__________________ Voiding Warranties  Taking Apart Gadgets and Building New Ones  
07202010, 11:04 PM  #45  
 
Class 1M Laser Join Date: Jun 2010
Posts: 164
Rep Power: 8 
I'm using 3 NiMH rechargeable AA batterys.
__________________ Notes to self: If you're bicycling backwards up a hill at a downwards speed of 37 miles per hour and it begins raining maple syrup how many pancakes does it take to shingle a dog house? Answer: onionbanana juice! The formula for finding the answer to any impossible question is onionbanana juice divided by the square root of infinity. Note safety features > If you don't understand the above ask jack sparrow.  
07242010, 04:46 PM  #46  
 
Class 3R Laser Join Date: Dec 2008 Location: Dallas, TX
Posts: 1,577
Rep Power: 128 
psi seeker 34; Remember that diode voltage matches up well with: 1. A 4.2VDC Lithiumion battery (the newest ones I have operate @ 4.35 VDC) 2. Three 1.5 VDC batteries with a small value resistor (try a 0.47 ohm to test current) Remember, that you must have a good heat sink for any directdrive system. LarryDFW
__________________ UV LED Lights F/S, 445nm, BluRays, Red 1/2W, Green Focusables, Link BluRay/445 Diode Test Current Levels for Long Life Last edited by LarryDFW; 12042011 at 03:18 AM.  
07262010, 04:07 AM  #47  
 
Class 1M Laser Join Date: Jun 2010
Posts: 164
Rep Power: 8 
My resistor is 2 ohm which is the lowest I could find in my pile of electronic scrap. If I want to go any lower I'll salvage a potentiometer to do the job so I don't have to keep soldering and unsoldering resistors to get the right one.
__________________ Notes to self: If you're bicycling backwards up a hill at a downwards speed of 37 miles per hour and it begins raining maple syrup how many pancakes does it take to shingle a dog house? Answer: onionbanana juice! The formula for finding the answer to any impossible question is onionbanana juice divided by the square root of infinity. Note safety features > If you don't understand the above ask jack sparrow. Last edited by psi seeker 34; 07262010 at 04:10 AM.  
07262010, 04:16 AM  #48  
 
Class 2M Laser Join Date: Jan 2008 Location: Maine, US
Posts: 673
Rep Power: 31  Quote:
You can also use an online resistor calculator instead for the calculation such as this one.
__________________ Voiding Warranties  Taking Apart Gadgets and Building New Ones Last edited by laser_freak; 07282010 at 09:23 PM.  
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