I need help from an electrical engineer ;<

[Chojin]

So I saw this thing online where you can make your own wireless wii sensor bar and decided it would be a FUN PROJECT. In the video, the dude uses a 4-pack AA battery, 4 infrared LEDs, a switch, and then just wires all the positives together on a perf board.

http://doctabu.livejournal.com/64758.html

I have two one-battery AA packs and two IR LEDs. I also got an extra switch and some red leds because I've never done this sort of crap before and my human eyes can see red ;<

My first design used the visible red LED and went one battery pack - red wire to switch prong 1 - another red wire from switch prong 2 to long LED prong - black wire from short LED prong to black wire on battery pack. Flipping the switch, nothing happens.

http://www.popnko.com/imock/perfboard.jpg

I imagine it's a problem with voltages and resistances not matching up, but I don't understand ohm's law well enough to make any sort of calculation here and I don't know what sort of power AA batteries produce. Ideally, here is my completed device: One AA battery pack to One AA battery pack to switch to IR LED to IR LED to One AA battery pack (return). In other words, two AA batteries powering two IR LEDs with a switch.

Oh and while we're at it could someone teach me how to use a perf board properly ;< I'm not using the lil contact rings at all ;<

OH I FORGOT here are the specs on the LEDs.

Infrared
Electrical characteristics (25 deg C)
Radiant power output (100mA): 16mW min.
Forward voltage: 1.2V
Forward current: 100mA
Viewing angle to 1/2 intensity: 45 deg

Absolute maximum ratings (25 deg C)
Forward voltage (20mA): 1.6V
Reverse voltage: 5V
Forward current: 1.2A
Reverse current: 10uA
Wavelength: 940nm

Regular Red
Absolute maximum ratings (at 25 deg C)
Power dissipation: 60mW
Forward current: 3.0VDC max.

Optoelectric characteristics (at 10mA)
Forward voltage: 2.6V
Luminous intensity: 10mcd
Peak wavelength: 650nm

[Mockery]

You forgot one vital part:

http://uk.gizmodo.com/fluxcapacitorebay.jpg

[FartinMowler]

first hook up the light/battery and switch so that you get the light to turn off and on...then transfer that idea to the board so it's a loop or bus of current through the board. A volt meter is nice to have for this. or even skip the board and just run a few lights in series with wire and hot glue them into the back of a small cardboard box.

[Chojin]

uh, like i said, i did just soldier everything together without really using the board ;<

[Archduke Tips]

Chojin,
It sounds like you hooked everything up correctly.

There is one glaring problem I see here though. 940nm is not within the visible light spectrum. The human eye can see light within the 400nm to 750nm spectrum.

So if it is lighting, you won't be able to see anything different.

Try putting a regular red LED in its place. If it lights when you flip the switch, then you will know everything is working properly.

[Chojin]

That's what I did, I hooked up a red LED first to see if it would work ;<

One battery, one led, one switch. Can you see something wrong there? :<

[Archduke Tips]

Perfboards basically are just one means to make your circuit a little bit neater. There really is no trick to them. If they are plated (meaning there is metal in each hole), then it is easier to solder onto.

Of course, you have to plan ahead if you want your circuit to actually look neat. You could just hookup the circuit without the perfboard and it would work fine so long as nothing shorts out.

[Archduke Tips]

The situation is resolved in case anyone is wondering. Here is what it turned out to be:

The red LEDs have a forward voltage of 3V, each battery is 1.5V. Therefore he needed two batteries to light the red LED.

But the IR LEDs have a forward voltage of 1.2V, so one battery is sufficient to light them.