Welcome to Laser Pointer Forums! If you are looking for a laser you may want to check out the database of laser pointer companies. The link will open in a new window for your convenience.

 Laser Pointer Forums - Discuss Laser Pointers resistors? Laser Pointer Company Database     Laser Top Sites List     Lasers by Type     Green Lasers

04-27-2009, 01:11 AM #1
 Junior Member Join Date: Apr 2009 Posts: 25 Rep Power: 0
Forgottenalarm
Junior Member

Join Date: Apr 2009
Posts: 25
Rep Power: 0
resistors?

so i have been looking forever and definalty decided to build a ddl driver for my PHR-803T Blu-Ray coming in the mail. i found about 5 diff resistor combos with the same other parts and im getting very confused.
i was wondering if someone can clairify for my what is the best combos to use?

here are the parts list of what the diag described that i have:
9 volt battery
switch
100 ohm pot
LM317 volt reg
2- 10 ohm resistors??????????????????????
1n4001 diode
35V cap

04-27-2009, 02:00 AM #2
 Class 3B Laser Join Date: Mar 2008 Posts: 2,658 Rep Power: 208
GooeyGus
Class 3B Laser

Join Date: Mar 2008
Posts: 2,658
Rep Power: 208
Re: resistors?

You choose resistors based on what you want your max current to be.

Use 1.25 (the voltage ref. value for the LM317) divided by your resistance to get max current. so 1.25 / 10ohm = .125A = 125mA so a 10ohm resistor will let you go no higher than 125mA.

7.5ohm worth of resistors will give you a 200mA max because 1.25 / 7.5 = .2A = 200mA

Hope that helped.

Oh yeah, two 10 ohm resistors gives you 5ohm total resistance if wired in parallel (like they usually are in the schematic) which will give you 1.25 / 5 = .25A = 250mA max current

04-27-2009, 05:42 AM #3
 Class 3R Laser Join Date: Dec 2008 Location: Dallas, TX Posts: 1,577 Rep Power: 127
LarryDFW
Class 3R Laser

Join Date: Dec 2008
Location: Dallas, TX
Posts: 1,577
Rep Power: 127
Re: resistors?

Forgottenalarm;

I use one 10 ohm resistor in my PHR builds with the #317 current reg.
That sets the current @ 125 ma.

The center terminal on the regulator is the output of the LM317.

Attached is a pictorial layout of the LM317 layout I modified for BluRay (125ma) from rog8811:

It has worked OK with no failures so far, in a good aluminum heat sink.

LarryDFW
Attached Thumbnails

Last edited by LarryDFW; 05-18-2009 at 01:35 AM.

04-27-2009, 08:54 AM #4
 Junior Member Join Date: Apr 2009 Posts: 25 Rep Power: 0
Forgottenalarm
Junior Member

Join Date: Apr 2009
Posts: 25
Rep Power: 0
Re: resistors?

got it, thanks guys. ima solder her up at work today. hopefully my laser will be here soon. order my goggles this weekend.

04-27-2009, 06:02 PM #5
 Junior Member Join Date: Apr 2009 Posts: 25 Rep Power: 0
Forgottenalarm
Junior Member

Join Date: Apr 2009
Posts: 25
Rep Power: 0
Re: driver testing

so my greeness is showing. i soldered up the driver. im only getting.20 volts difference with adjusting the pot. from 7.5x to 7.3x. i thought the pot controlled more of the voltage/ current then that?? im trying to find a suitable testing source. all i can find is a pr3 flashlight bulb which isnt doing anything and the only multimeter i could find only tests volts.

04-27-2009, 07:15 PM #6
 Class 3B Laser Join Date: Jul 2007 Location: Berkshire UK Posts: 2,759 Rep Power: 193
rog8811
Class 3B Laser

Join Date: Jul 2007
Location: Berkshire UK
Posts: 2,759
Rep Power: 193
Re: resistors?

The voltage won't change much it is the current you need to measure.
Make a test load with 6 diodes for the load and a 1ohm resistor as a shunt, measure the volts across the resistor with the meter set to mv and you get the current in ma.

Regards rog8811
Attached Thumbnails

__________________
See all of my videos on Vimeo
http://www.vimeo.com/4454150

Lots of tutorials and information on lasers
http://www.rog8811.com/

In the land of the blind the one eyed man..... is most likely holding the laser

04-27-2009, 07:55 PM #7
 Junior Member Join Date: Apr 2009 Posts: 25 Rep Power: 0
Forgottenalarm
Junior Member

Join Date: Apr 2009
Posts: 25
Rep Power: 0
Re: resistors?

k great thanks. p.s. got my laser in the mail [smiley=2vrolijk_08.gif]

04-28-2009, 02:22 AM #8
 Junior Member Join Date: Apr 2009 Posts: 25 Rep Power: 0
Forgottenalarm
Junior Member

Join Date: Apr 2009
Posts: 25
Rep Power: 0
Re: resistors?

tested about 21-123ma. so i went for it. *and it is the most vibrant color i have ever seen in my life. i turned up for the few seconds i had it on about 2 minutes apart as to not burn out the ld.

but yet this is only the begining.

i still need a glass lens and goggles.
create a labby host with fan and swap out the 10 ohm resistor to a 5 ohm while reworking the
pcb to a breadboard for better componant testing/learning as well as placemant.

shall we take bets to see how long the lens lasts? *:

04-28-2009, 05:04 AM #9
 Class 1M Laser Join Date: Feb 2009 Posts: 201 Rep Power: 19
proud2deviate
Class 1M Laser

Join Date: Feb 2009
Posts: 201
Rep Power: 19
Re: resistors?

You don't need an IR filter. That's just for DPSS systems, like green, blue, and yellow. Violet laser diodes emit no IR light. For your glass lens, make sure that it's anti reflective coated for the proper wavelength. The Aixiz lens is not good for 405 nm.

Looks like you've got the rest pretty well figured out. Best of luck!
__________________
Lasers, like most electronic devices, run on smoke. Once the smoke gets out, they don't work anymore.

An important reminder; ">500mW of a high-energy wavelength will decompose organic materials on contact." - RA_pierce

04-28-2009, 11:40 AM #10
 Junior Member Join Date: Apr 2009 Posts: 25 Rep Power: 0
Forgottenalarm
Junior Member

Join Date: Apr 2009
Posts: 25
Rep Power: 0
Re: resistors?

yeah i found a little more info on that late last night.
good lookin out man!

i think im going to build a heatsink so i dont have to buy one.. i have some thermal compound at home. thats a little more saved up for the glass lens...

04-28-2009, 09:09 PM #11
 Class 2 Laser Join Date: Dec 2008 Posts: 282 Rep Power: 25
milantheone
Class 2 Laser

Join Date: Dec 2008
Posts: 282
Rep Power: 25
Re: resistors?

i have also made a calculator for DDL driver, which should help you to calculate a value of two or three resistrors in parallel connection... plus you will get also a rough estimation of a mA.....

i hope this will help to someone
Attached Files
 ddl_driver_rescalculator_parallel_connection.zip (6.1 KB, 38 views)

04-29-2009, 01:40 PM #12
 Junior Member Join Date: Apr 2009 Posts: 25 Rep Power: 0
Forgottenalarm
Junior Member

Join Date: Apr 2009
Posts: 25
Rep Power: 0
Re: resistors?

it would help, but i dont have excell. thanks anyman.

04-29-2009, 03:34 PM #13
 Class 2 Laser Join Date: Dec 2008 Posts: 282 Rep Power: 25
milantheone
Class 2 Laser

Join Date: Dec 2008
Posts: 282
Rep Power: 25
Re: resistors?

Quote:
 Originally Posted by Forgottenalarm it would help, but i dont have excell. thanks anyman.
that sucks..
anyway, maybe it will help to someone else.. *i should aslo post this calcurator to the original thread about DDL driver, but i am tooo lazy at the moment to seach it.. *:P

05-01-2009, 03:21 PM #14
 Junior Member Join Date: Apr 2009 Posts: 25 Rep Power: 0
Forgottenalarm
Junior Member

Join Date: Apr 2009
Posts: 25
Rep Power: 0
Re: resistors?

Here is my laser at about 130 ma.

found a descent size piece of aluminum and drilled it out, installed some thermal compount that i was using for my processor installation in my pc. now all i need is a 5 ohm resistor and i will remake the driver to support more heat. (IE. heat sink on the L317T, more space between componants, and a fresh pot.)
Attached Thumbnails

05-13-2009, 05:03 AM #15
 Class 3R Laser Join Date: Dec 2008 Location: Dallas, TX Posts: 1,577 Rep Power: 127
LarryDFW
Class 3R Laser

Join Date: Dec 2008
Location: Dallas, TX
Posts: 1,577
Rep Power: 127

Forgottenalarm;

The 130 ma you are operating at, is a good level, if you want to keep your BR diode operating.

By going to 5 ohms, you will go to 250 ma of current, which is too high for the optical mirrors of your diode.

A larger heatsink will not allow operation at that level.

I do know where you can get a good Hi-Power lens assembly

LarryDFW

Last edited by LarryDFW; 09-08-2009 at 02:03 AM.

05-14-2009, 01:32 AM #16
 Junior Member Join Date: Apr 2009 Posts: 25 Rep Power: 0
Forgottenalarm
Junior Member

Join Date: Apr 2009
Posts: 25
Rep Power: 0

yeah i realized that a little later on. i have some feelers out now finding me some drives that are no good anymore- well to 99% of everyone else anyway. from there i will harvest more powerfull lasers to experiment with. if i ever scrape up enough cash i will just toss the phr in a host and whip it out for the nice foggy nights up in the woods in the country.

but on a side note, you ever shine one of those on hunter orange. its pretty looking.

Last edited by Forgottenalarm; 05-14-2009 at 01:33 AM. Reason: cant type for shit

 Thread Tools Display Modes Linear Mode

 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 OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

All times are GMT. The time now is 01:14 PM.

 -- DarkShadows V5 -- Responsive LPF -2562016 -- Default Style Contact Us - Laser Pointer Forums - Archive - Top