Laser pointer discussion. Read/write reviews of laser pointers and laser pointer companies. Learn about all types of laser pointers and lasers





Welcome to Laser Pointer Forums! If you are looking for a laser pointer or want to compare different laser pointer companies, you may want to check out the LPF Laser Pointer Company Database. The link will open in a new window for your convenience.








Green Laser Pointers by Category Blue Laser Pointers by Category Red Laser Pointers by Category
Yellow Laser Pointers by Category Violet Laser Pointers by Category Orange Laser Pointers by Category
Top Laser Pointers by Power - 1 Watt+ Top Laser Pointers by Power - 500mW+ Top Laser Pointers by Power - 250mW+
Laser Pointer Database High Power Laser Pointers Laser Pointer Diodes
Laser Technology Laser Pointer Parts Lasers by Wavelength
Top 10 Laser Pointer Companies Laser Pointer Company Database Visible Beam Laser Pointers


One laser store meets all your needs

























Go Back   Laser Pointer Forums - Discuss Laser Pointers > Lasers > Experiments & Modifications



LPF List of Laser Pointer Companies (link opens new window)



Reply
 
LinkBack Thread Tools Display Modes
Old 01-09-2008, 11:14 PM #193
roSSco's Avatar
Class 2M Laser
 
Join Date: Dec 2007
Posts: 649
Rep Power: 14
roSSco is a jewel in the roughroSSco is a jewel in the roughroSSco is a jewel in the rough
roSSco roSSco is offline
Class 2M Laser
roSSco's Avatar
 
Join Date: Dec 2007
Posts: 649
Rep Power: 14
roSSco is a jewel in the roughroSSco is a jewel in the roughroSSco is a jewel in the rough
Default Re: DIY Laser Torch

Does that last pic say .25ma ? If so, where did you measure it?


roSSco is offline   Reply With Quote







LPF List of Laser Pointer Companies (link opens new window)







Old 01-09-2008, 11:25 PM #194
Gazoo's Avatar
Class 3B Laser
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Gazoo Gazoo is offline
Class 3B Laser
Gazoo's Avatar
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Default Re: DIY Laser Torch

It says 250ma's. I find it strange though since he is powering a red LED. And it is being run off of 4 batteries, this driver needs six.
Gazoo is offline   Reply With Quote
Old 01-09-2008, 11:27 PM #195
knimrod's Avatar
Class 2 Laser
 
Join Date: Nov 2007
Location: Lansing, MI
Posts: 384
Rep Power: 13
knimrod is a jewel in the roughknimrod is a jewel in the roughknimrod is a jewel in the rough
knimrod knimrod is offline
Class 2 Laser
knimrod's Avatar
 
Join Date: Nov 2007
Location: Lansing, MI
Posts: 384
Rep Power: 13
knimrod is a jewel in the roughknimrod is a jewel in the roughknimrod is a jewel in the rough
Default Re: DIY Laser Torch

Something can't be right.. *You can't source 250mA into a standard LED without it blowing up... *And you meter is saying .25mA (250uA).

I use a 10 ohm, 1/2 watt resistor as a dummy load usually. *You can just *measure the voltage across this resistor and the and the current will be I=V/10. *So.. 2.5V would equal .25A. *
__________________
I never give them hell. I just tell the truth and they think it's hell. - Harry S. Truman
knimrod is offline   Reply With Quote
Old 01-09-2008, 11:34 PM #196
knimrod's Avatar
Class 2 Laser
 
Join Date: Nov 2007
Location: Lansing, MI
Posts: 384
Rep Power: 13
knimrod is a jewel in the roughknimrod is a jewel in the roughknimrod is a jewel in the rough
knimrod knimrod is offline
Class 2 Laser
knimrod's Avatar
 
Join Date: Nov 2007
Location: Lansing, MI
Posts: 384
Rep Power: 13
knimrod is a jewel in the roughknimrod is a jewel in the roughknimrod is a jewel in the rough
Default Re: DIY Laser Torch

Quote:
Originally Posted by Gazoo
It says 250ma's. I find it strange though since he is powering a red LED. And it is being run off of 4 batteries, this driver needs six.
Look closer.. he's using the meter for measuring current. The display says "mA". He may have the probe leads in the wrong hole in the meter or something.

One thing's for sure... He's can't really be putting a half watt into that LED.. There's no smoke in the picture..
__________________
I never give them hell. I just tell the truth and they think it's hell. - Harry S. Truman
knimrod is offline   Reply With Quote
Old 01-10-2008, 12:15 AM #197
Gazoo's Avatar
Class 3B Laser
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Gazoo Gazoo is offline
Class 3B Laser
Gazoo's Avatar
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Default Re: DIY Laser Torch

I guess I am used to my meter because I have mine on the 10 amp scale when measuring current...so 250ma's would show as 0.25ma's. If he is measuring on the 200ma scale then it would show as 25ma's. So I am confused.. ;D

I do like this diagram. IMO it is one of the easiest to follow:

Gazoo is offline   Reply With Quote
Old 01-10-2008, 12:20 AM #198
Class 1M Laser
 
Join Date: Jan 2008
Posts: 150
Rep Power: 13
troop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the rough
troop231 troop231 is offline
Class 1M Laser
 
Join Date: Jan 2008
Posts: 150
Rep Power: 13
troop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the rough
Default Re: DIY Laser Torch

Ok, I noticed with 250ma going into the LED, that it was really hot. Then I tried it later with 2 others and fried them. I took 1 resistor out giving me 10 ohms instead of 5 ohms. Now I got a 140-150ma range. This seem about right? Also, when I go to measure the ma output, why will the LED go out completely, then when I remove the voltmeter, it will turn back on? Thanks again! 8-)
troop231 is offline   Reply With Quote
Old 01-10-2008, 12:24 AM #199
Gazoo's Avatar
Class 3B Laser
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Gazoo Gazoo is offline
Class 3B Laser
Gazoo's Avatar
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Default Re: DIY Laser Torch

Sounds like you have your meter in parallel with the output...this is a big no..no. Your meter needs to be in series with the output.
Gazoo is offline   Reply With Quote
Old 01-10-2008, 12:26 AM #200
Class 1M Laser
 
Join Date: Jan 2008
Posts: 150
Rep Power: 13
troop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the rough
troop231 troop231 is offline
Class 1M Laser
 
Join Date: Jan 2008
Posts: 150
Rep Power: 13
troop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the rough
Default Re: DIY Laser Torch

Um, can you explain please? That confuses me. A diagram showing where I should measure with my voltmeter would be great!
troop231 is offline   Reply With Quote
Old 01-10-2008, 12:29 AM #201
knimrod's Avatar
Class 2 Laser
 
Join Date: Nov 2007
Location: Lansing, MI
Posts: 384
Rep Power: 13
knimrod is a jewel in the roughknimrod is a jewel in the roughknimrod is a jewel in the rough
knimrod knimrod is offline
Class 2 Laser
knimrod's Avatar
 
Join Date: Nov 2007
Location: Lansing, MI
Posts: 384
Rep Power: 13
knimrod is a jewel in the roughknimrod is a jewel in the roughknimrod is a jewel in the rough
Default Re: DIY Laser Torch

You can use your multimeter (setup to read current) in series with the input. *Connect the positive lead of the meter to the positive lead of your power source, and the negative lead of the meter to the power (positive) input lead of your regulator circuit.
__________________
I never give them hell. I just tell the truth and they think it's hell. - Harry S. Truman
knimrod is offline   Reply With Quote
Old 01-10-2008, 12:36 AM #202
Class 1M Laser
 
Join Date: Jan 2008
Posts: 150
Rep Power: 13
troop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the rough
troop231 troop231 is offline
Class 1M Laser
 
Join Date: Jan 2008
Posts: 150
Rep Power: 13
troop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the rough
Default Re: DIY Laser Torch

Don't I want to measure after the resistors though? Diagram please? ;D
troop231 is offline   Reply With Quote
Old 01-10-2008, 12:49 AM #203
Class 1M Laser
 
Join Date: Jan 2008
Posts: 150
Rep Power: 13
troop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the rough
troop231 troop231 is offline
Class 1M Laser
 
Join Date: Jan 2008
Posts: 150
Rep Power: 13
troop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the rough
Default Re: DIY Laser Torch

Ug, I just burnt some more LEDs trying to figure where to measure the correct way. Anyone got some ideas?
troop231 is offline   Reply With Quote
Old 01-10-2008, 12:49 AM #204
knimrod's Avatar
Class 2 Laser
 
Join Date: Nov 2007
Location: Lansing, MI
Posts: 384
Rep Power: 13
knimrod is a jewel in the roughknimrod is a jewel in the roughknimrod is a jewel in the rough
knimrod knimrod is offline
Class 2 Laser
knimrod's Avatar
 
Join Date: Nov 2007
Location: Lansing, MI
Posts: 384
Rep Power: 13
knimrod is a jewel in the roughknimrod is a jewel in the roughknimrod is a jewel in the rough
Default Re: DIY Laser Torch

Quote:
Originally Posted by troop231
Don't I want to measure after the resistors though? Diagram please? *;D
In a series circuit, the current is the same everywhere.


Power Source ** * * * * * * * * Amp Meter * * * * * * * Regulator Circuit
------------- *** * * * * * * *---------- * * * * * * * *-----------
| * * ** * +|-----------o<-----|+ * * *-|----->o---------|+ * * * *|
| * * ** * *| * * * * * * * * *| * * * *| * * * * * * * *| * * * * |
| * * ** * *| * * * * * * * * *| * * * *| * * * * * * * *| * * * * |
| * * ** * *| * * * * * * * * *| * * * *| * * * * * * * *| * * * * |
| * * ** * *| * * * * * * * * *| * * * *| * * * * * * * *| * * * * |
| * * ** * *| * * * * * * * * *---------- * * * * * * * *| * * * * |
| * * ** * -|--------------------------------------------|- * * * *|
------------- * * * * ** * * * * * * ** * * * * * * * * *-----------
__________________
I never give them hell. I just tell the truth and they think it's hell. - Harry S. Truman
knimrod is offline   Reply With Quote
Old 01-10-2008, 12:52 AM #205
Class 1M Laser
 
Join Date: Jan 2008
Posts: 150
Rep Power: 13
troop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the rough
troop231 troop231 is offline
Class 1M Laser
 
Join Date: Jan 2008
Posts: 150
Rep Power: 13
troop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the rough
Default Re: DIY Laser Torch

Woah that confused me even more lol. Can you just point out in my pics where to measure? That would be fantastic! Thanks!
troop231 is offline   Reply With Quote
Old 01-10-2008, 12:52 AM #206
knimrod's Avatar
Class 2 Laser
 
Join Date: Nov 2007
Location: Lansing, MI
Posts: 384
Rep Power: 13
knimrod is a jewel in the roughknimrod is a jewel in the roughknimrod is a jewel in the rough
knimrod knimrod is offline
Class 2 Laser
knimrod's Avatar
 
Join Date: Nov 2007
Location: Lansing, MI
Posts: 384
Rep Power: 13
knimrod is a jewel in the roughknimrod is a jewel in the roughknimrod is a jewel in the rough
Default Re: DIY Laser Torch

Quote:
Originally Posted by troop231
Ug, I just burnt some more LEDs trying to figure where to measure the correct way. Anyone got some ideas?
LEDs are not going to work for you unless you use a bunch in parallel.. *If you have an extra 10 ohm resistor, you can use it for a dummy load as I mentioned earlier. Then you can just measure the voltage across the dummy load to discern the current.

Also, Gazoo was right.. Your power source is really inadequate for this circuit..
__________________
I never give them hell. I just tell the truth and they think it's hell. - Harry S. Truman
knimrod is offline   Reply With Quote
Old 01-10-2008, 12:55 AM #207
Gazoo's Avatar
Class 3B Laser
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Gazoo Gazoo is offline
Class 3B Laser
Gazoo's Avatar
 
Join Date: Jun 2007
Location: Dallas Tx
Posts: 3,199
Rep Power: 180
Gazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond reputeGazoo has a reputation beyond repute
Default Re: DIY Laser Torch

Actually measuring between the power source and the circuit is a good idea. The current measured will be the same. I think it was chimo that reminded us of kirchoff's law.

Follow knimrod's instructions...or google it.

how to use a dmm
Gazoo is offline   Reply With Quote
Old 01-10-2008, 01:18 AM #208
Class 1M Laser
 
Join Date: Jan 2008
Posts: 150
Rep Power: 13
troop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the rough
troop231 troop231 is offline
Class 1M Laser
 
Join Date: Jan 2008
Posts: 150
Rep Power: 13
troop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the roughtroop231 is a jewel in the rough
Default Re: DIY Laser Torch

OK, does this look right? If not, point out where it should go? Thanks!

troop231 is offline   Reply With Quote
Reply





Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


LinkBacks (?)
LinkBack to this Thread: http://laserpointerforums.com/f42/diy-laser-torch-26402.html
Posted By For Type Date
DIY Laser Torch - Laser Pointer Forums - Laser Pointers and Laser ... - Peg It Board This thread Refback 01-04-2013 07:10 PM
Blummin' neighbours!! - Stargazers Lounge This thread Refback 04-18-2011 02:44 PM
Bl**by neighbours!! - Stargazers Lounge This thread Refback 04-18-2011 08:01 AM










Loading








Green Laser Pointers by Category Blue Laser Pointers by Category Red Laser Pointers by Category
Yellow Laser Pointers by Category Violet Laser Pointers by Category Orange Laser Pointers by Category
Top Laser Pointers by Power - 1 Watt+ Top Laser Pointers by Power - 500mW+ Top Laser Pointers by Power - 250mW+
Laser Pointer Database High Power Laser Pointers Laser Pointer Diodes






Privacy Policy | Advertising Disclaimer | Terms of Use


 


All times are GMT. The time now is 02:52 PM.


Powered by: vBulletin
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO
Privacy Policy | Advertising Disclaimer | Terms of Use
Copyright (C) 2017 Laser Pointer Forums, LLC