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lawrence #16 26/01/2012 - 06h47

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this is what the pack says on it
5mm
yellow LED
3vdc-20mA-55mcd
on the back of packit says:
peek emmision wave length 585typ
veiwing angle 40
dewey1 #17 26/01/2012 - 08h49

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So why are you using yellow LEDS?

The Vf maximum is 3 V. Typical is 2.1 V
The maximum current is 20mA. Far from the 3 A you mentioned.

Do yourself a big favor and use IR LEDS like the SH485P.
Use 33 Ohm 1/4 W or 1/2 W for each LED if using 3 V parallel circuit.

http://forum.free-track.net/index.php?showtopic=1856

DigiKey is a great vendor for US customers.

Check this for simple on/off 2-AA battery holder;
http://search.digikey.com/us/en/products/SBH321AS/SBH321AS-ND/275301

IR LEDs;
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=475-1470-ND

I purchased 10 SFH485P for $6.81 including shipping ($2.07) from Digi-Key.
So I got 7 spares to build clips or hats. There was a price break at 10 pieces.
10 pcs for $.44 each or 1-9 for $.77 each. Almost twice as many for same price. (10 versus 5)
Edited by dewey1 on 26/01/2012 at 08h53.
Steph #18 26/01/2012 - 11h52

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ok since you know what your talking about get a job at radio shack that  leds i got have a 3 amp max  the guy told me that two doudle a batterys will work just fine without resisters i dont mind replacing them from time to time  oh and i had 33ohm resisters hooked up before and the leds would not work but ill give it a tr if you insist



Well, I suppose your guy got a well working freetrack headmount,
hm...otherwise I'm sure dewey1 got one and mine works fine too, like many others here in the forum.
Freetrack mounts are quit simple elecronics and not a big thing even for beginners if you accept and follow some simple advises, read some informations given in multiple threads and ask specific questions.


does that web cam need to be modified in any way or will it work like it comes right out the box



You can have a try first without modification and a good daylight-Filter (floppy disk etc.) otherwise:

http://forum.free-track.net/index.php?showtopic=2633&message=14351
lawrence #19 27/01/2012 - 00h18

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im using two AA batterys to power my head set if it be sugested i do have some 33ohm resisters i can add to it if you think it will help as far as using the yellow LED ive seen videos of all diffrent colors that were used im heading down tomarrow to pic up a new web cam that is compatable with the program
Steph #20 27/01/2012 - 10h12

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If you used yellow LEDs you don't need to modify your webcam, but you can't used your mount in daylight conditions. You only can use it in a dark room, without any other light-source  in front of the cam.
Therefore it is advantageous to use infra-red LEDs, allowing you to use Freetrack tracking in any conditions.
dewey1 always gives you the best reference for ir LEDs:
IR LEDs;
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=475-1470-ND
lawrence #21 27/01/2012 - 21h09

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well ok i dont have the resorces to order online so i have to go to the local radio shack they have all kinds there. is it recamended that i just use white or does the color mater
Steph #22 29/01/2012 - 13h39

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I'm not sure you have understand the sense for using IR (infra-red) LEDs.

For reasons of efficiency, FreeTrack requires the tracking points to be isolated from all other light, this is best done using infrared LEDs and a visible-light blocking filter in front of the camera. Photographic film or the magnetic storage medium inside floppy disks can be used as inexpensive visible-light filters. Further filtering can be done in software by adjusting exposure and threshold.
All video devices like webcams have a built-in infrared blocking filter which can be removed to improve sensitivity to infrared light, allowing better point isolation and the possibility of retroreflective tracking. This is normally a straightforward and reversible procedure for most webcams.


Source Wikipedia

The color of IR-LEDs is in infra-red wavelength, so you can't see it.
If radio shack do not have the SFH 485 P ask for some other Ø5mm IR-LEDs with high beam angle.
dewey1 #23 30/01/2012 - 20h08

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lawrence @ 27/01/2012 - 21h09 a dit:

well ok i dont have the resorces to order online so i have to go to the local radio shack they have all kinds there. is it recamended that i just use white or does the color mater


Use these:
http://www.radioshack.com/product/index.jsp?productId=2062565

The LEDS will probably need to have the lens sanded and polished to increase beam angle.

Series circuit with USB power:
1.28 x 3= 3.84
5.0-3.84=1.16
1.16/.05=23.2 Ohms for 50 mA

Use a 1/2W 5% resistor in the range of 20 Ohm to 22 Ohm.

20 Ohm will be 58 Ma current.
22 Ohm will be 53 Ma current.

You could use 10 Ohm resistors and series wire for 20 Ohm.
lawrence #24 01/02/2012 - 18h09

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went out a got the right stuff every thing i got is by the book ended up getting the logitech C510 it was on the list and wal-mart had it does the IR Filter need to be removed didnt say on web page. i hooked it up turned on my head set and the free track software worked at first when i had my bedroom light on i could see red then i turned it off and nothing showed up
im getting 30FPS NOW VS 8
dewey1 #25 01/02/2012 - 20h01

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lawrence @ 01/02/2012 - 18h09 a dit:

went out a got the right stuff every thing i got is by the book



What does that mean? Care to explain better?

IR-LEDS?
Series 3 LED?
What power source?
What resistor values?

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