I tried making my own sensor bar as well, but it seems to be dead.
I used a 33 Ohm resistor in series with two Radio Shack IR LEDs and 4 AAAs + switch.
Voltmeter says the connections are good but the Wiimote does not see it. It worked for a bit, but after I squeezed it in a box it seems dead.
Think I burned out the LEDs? Wrong resistor?
Or did I break a contact and I don't know how to use a voltmeter?
My background is chemistry+computer, so solder and electricity is sketchy...