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RSS >  equivalent resistance
WarriorWulf #1 23/07/2016 - 21h15

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Hi all,

I had a question about the wiring of the leds and resistors, lets say the calculator tells me to use three resistors for three leds and instead I want to place only one resistor with the formula to calculate the equivalent resistance.
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If we use 1/R = 1/R1 + 1/R2 + 1/R3, is it then not possible to use only one? Is there a special reason to do it with three? Can I build it in serial?
Edited by WarriorWulf on 23/07/2016 at 21h24.
Stormrider #2 23/07/2016 - 21h51

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with three resistors you also share the dissipated power(heat) over the three of them.And what if one of your leds has a small variation in internal resistance.
If you want to use 80mA as forward current for each led, this means one resistor has to deal with 0,24A
I personal think the best model is made with usb power(5Volt) and paralel circuit.That ptc is not needed.
You can use a powerbank which are used for charching smartphones as a wireless powersource.
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WarriorWulf #3 23/07/2016 - 22h01

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Thanks for the reply dude its just what i wanted to know.
Stormrider #4 23/07/2016 - 22h17

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Do you know that freetrack is not the only ir-tracking software?It is the oldest and no more updated.Even though it can work on win7/8/10 it still can give you some problems.The others can be found here and are still updated:
opentrack    https://github.com/opentrack/opentrack/releases
For Facetracknoir the developer askes a small fee,a very small compensations for tons of pleasure.
http://www.facetracknoir.nl/
Edited by Stormrider on 23/07/2016 at 22h21.
WarriorWulf #5 23/07/2016 - 22h23

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I did not, thank you for the info!
Stormrider #6 23/07/2016 - 22h38

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and something instead of ir-tracking.
http://www.edtracker.co.uk/
You can built it yourself or purchase it ready to use.

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