FreeTrack Forum

Hey everybody, found out about this on the Simhq forums.  I was very intrested in this system and wanted to build my own.  I do have a couple questions before I make the plunge in to building.  Will the head set work if I make it out of led out of a remote control?  I happen to have a couple remotes around the either the buttons aren't read able or they were replace with a new one.    They both used triple A batteries.  What kind of voltage or is it ampage would they use?  If I know that then I can figure out what kind of resistor to use.  One more question and that is what kind of power supply is recommended?  Battery pack of some sort or a plug in type (not sure how I would hook something like that up but one problem at a time)
Thanks for your time and Help
BigJohn

Hi and welcome !

to help you to solved your question about freetrack model, you can use this link :

http://www.free-track.net/english/hardware/calcled/

After that, if you need more help about electronic, you can contact Tristan68.

We recommanded to use LED SFH485P , you can find more informations about these LEDs on our forum ! (because Wide angle 80° is better for tracking !)

Voltage and MA depending of your type of led and type of alimentation.
For standard SHF485p (by LED)  :   1,5v   70Ma ...    (i recommanded to use Two LR6 batterie (serial plug) - it's easy to build, easy to replace, easy to find, low cost, easy to move and it's less dangerous for your motherboard computer than USB)

You can read this topic to have more informations :
http://forum.free-track.net/index.php?showtopic=413

English documentation is included with Freetrack software ! Read it before to start !
I think it's easy to understand (it's babasior opinion   ... so this not an objective opinion      )
There are some examples in documentation ...

It is pretty strait forward, John.

There is alot of room for "i cant make that, so i do it this way"

-so if you got 3 remotes, and the can make a Constant light (pressing the what ever button), and the all run on 2 AA batteries. then wire up the battery compartments together, and stick them on a hat -insert 2 batteries, and test.

If that works, gut the remotes, strip them down. -make it pretty.

My setup is made from a LED (red) Bike-rear-light, 6 thin wires, and a Piano-wire to get the top LED up high. And it works great. -so good that it tracks perfect even in daylight. -so good, that the only reason for going IR should be, that the pedestrians, outside my inner city flat -does not look at me like a complete Jerk wearing a Black cap, with 3 RED lights on (when i look outside).

-and the support, is SUPERB in here

Thanks for the help so far.  I have learn a couple of things as I am fumbling in my attempt to build a cap.  The first thing I have learned is that if you accidently put to much power to a LED  even for a second they stink something fierce (LED's still seem to work)  The next thing I have learned is that I suck at soldering  yet again don't hold a soldering gun to long on the LEDs leads (stink city again).   Any way I finally got every thing together.

But when I turn my switch on I might get one LED to show up on the Camera.

(I am using 4 AAA batteries,  stock logitech quickcam, no filter)

I estimated that the LED are around 1.2 volts each which equals 3.2 volts.

At first I had two 10ohm resistors in series to get me near the required 22 ohm resistance, but I did not seem to get any power through the wires.  So I took a resistor out, and yet no power.  A LED would sometimes show up on the camera but never all of them if held up at the same time.  Any one have any ideas what my problem is.  I picked up some IR LEDs from a local radio shack they will be for my final one once I get the kinks out.  So I am using there spec for my test rig. Forward voltage of 1.2V, forward Current of 100mA, wavelength of 940nm, and 5mm for diameter.  Any ideas, I really want to get one working but am getting confused on what I am doing wrong.  Thanks for any help

BigJohn

Howdy Big John,
   Noticed you're having problems getting your LED's to fire.  One issue is that LED's only light up when the polarity of the current runs in the correct direction. Check that you have connected them right way around.

As far as your curcuit setup.

I'll construct a series circuit equation for you:
Resistor value = 6 volts from batteries - 3.6 volts required by the LED's / .1A
Resistor value = 2.4 volts / .1A
Resistor value = 24 ohm

But you don't really need to use 4 batteries.... you can use 3:
Resistor value = 4.5 volts from batteries - 3.6 volts required by the LED's / .1A
Resistor value = .9 volts / .1A
Resistor value = 9 ohm

You appear to be using the correct resistor, just check into the polarity of the LED's.

Good Luck,
Christopher