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RSS >  Easy build setup with SFH485P, Anyone can build this !   (for 5v Usb serial build see Page 2)
doveman #181 09/09/2012 - 13h29

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Thanks, that's a useful diagram. I'll see what I can do.
norsk2277 #182 09/09/2012 - 19h10

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Hey guys! can i use this led?

SFH 487P
https://www.elfaelektronikk.no/elfa3~no_no/elfa/init.do?item=75-281-45&toc=20386

and what resistor should i use?

and what film should i use? type? a cheap on that is good
Edited by norsk2277 on 09/09/2012 at 19h42.
Steph #183 10/09/2012 - 12h06

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The  SFH487p isn't that good, because of little Ø3mm and low radiation intensity.
If you can't get the SFH485p (Ø5mm) than go for any other Ø5mm with high beam angle and high radiation intensity.
Like this one:
https://www.elfaelektronikk.no/elfa3~no_no/elfa/init.do?item=75-201-58&toc=20386

You need to file them down to increase the beam angle:

Posted Image
Edited by Steph on 08/11/2012 at 10h13.
norsk2277 #184 10/09/2012 - 16h45

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So the SFH 485-2 is good? i just fil it down?

And what resistor should i use? 10 Ohm
Steph #185 10/09/2012 - 19h38

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Get these both:
https://www.elfaelektronikk.no/elfa3~no_no/elfa/init.do?item=75-119-04&toc=20386&name=ir-led_950_nm_5_mm_%28t1.%29,_ld_274
and

https://www.elfaelektronikk.no/elfa3~no_no/elfa/init.do?item=75-201-58&toc=20386


I know the LD 274 are all right (if you file them down). I have used them myself . But the SFH485-2 have a better beam angle. Should be working without modification.
Otherwise file them down about 1mm above the cathode (like on the photo) and polish with sandpaper (800-1000). It don't have to be clear transparent.

Resistor depends on voltage. Go for the serial 5V build like the first post of this topic and get some 6.8 ohms and 10 ohms (for higher light intensity). (They aren't expensive).
norsk2277 #186 10/09/2012 - 21h22

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okey i have got 1 piece 10ohm for the 5V in usb cable i will use and i will buy the leds 3 pieces. is it ok? with the resistor?
Steph #187 10/09/2012 - 22h02

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It's okay, but if you command on net anyway, getting some extra resistors for 20cents, will not ruin you. :)

(Better use a USB-charger for powering your mount. Wrong wiring can blast up your motherboard. ;)
norsk2277 #188 10/09/2012 - 22h53

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2 piec resistor? 10 ohm and it should be ok? what happend i only use the one?
i will use power from USB charger
Steph #189 11/09/2012 - 13h34

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No, sorry I didn't explain myself enough. :gene:
With 5V in serial circuit you have the choice to use one 10 Ohm resistor giving you 50mA - LEDs are at 50% of max.100mA.
Or you can use one 6.8 Ohm resistor to let 75 mA flow and your LEDs will be brighter.
It's just an option if you got problems with light intensity of your LEDs.
mireazma #190 11/09/2012 - 15h06

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So fast flash: parallel LED's wiring has the downside of stressing the remaining ones, once one wants to die (read it loud, hehe). Upside: no of batteries needed.

But I'm confused: why not put 1 resistor before branching instead of 3, 1 on each branch?
Edited by mireazma on 11/09/2012 at 15h16.
norsk2277 #191 14/09/2012 - 09h57

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So do i need to buy both types of IR led? or
i think using 3 IR leds on 10 Ohm reistor. is it any other website? with free shipping, do dealextreme have IR led or the black Film?
Edited by norsk2277 on 14/09/2012 at 10h06.
Steph #192 14/09/2012 - 14h12

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You do not, but you will have more postage than invoice.
They are not very expensive and you can use them for your next build. ;)

is it any other website?



Which country?
benmeijer #193 15/09/2012 - 13h36

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mireazma @ 11/09/2012 - 15h06 a dit:


....
But I'm confused: why not put 1 resistor before branching instead of 3, 1 on each branch?


Google and you will find your answers ... I found this

answer Frollard:
Running multiple leds in parallel with only one resistor in series is a bad plan because each led is essentially a short circuit - and only a SLIGHT variation between manufactured leds will mean one will draw more current than the others - leading to it being brighter - and getting slightly hotter. The hotter it gets, the less it resists, the more power flows, and it quickly becomes a completely short circuit until it burns out.
EVERY parallel circuit needs its own series resistor


@Steph and @dewey1:

Thanks for your support in this topic !!!
Edited by benmeijer on 15/09/2012 at 13h39.
norsk2277 #194 20/09/2012 - 17h58

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Can i use film that is black on the front side and old collor on the bakside?
Steph #195 21/09/2012 - 13h49

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Only developed, unexposed Film really works fine:
http://www.pixiq.com/article/create-your-own-ir-filter





@Steph and @dewey1:

Thanks for your support in this topic !!!



No problem. ;)
Edited by Steph on 21/09/2012 at 13h50.

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