Custom adjustable sensor bar tutorial

[iceblade]

If someone who has electronic experience could post a tutorial for a custom sensor bar it would be greatly appreciated. I think it would be practical if you could change the distance between the two IR sources (eg having separate IR sources). This is very useful for projector setups.
I have two questions though.
1)I'm planning on building two IR sources each of which would have 5 IR LEDs, 2AA batteries, 1 battery holder to put em in and one resistor. What resistor do you think I should use to get a balance of output power and play time (approx 10hr for 2AAs if fine for me 15-20 better of course. But i would like enough power for a 30 feet range.
2) What is that white material that guy in this youtube video puts on the battery holder?

sorry for posting new topic, tried replying to an old about the sensor bar but i wouldn't let me because it's too old

 

[mikeomatic2]

candles lol just go to youtube for this

 

[iceblade]

candles lol just go to youtube for this

dude...seriously

 

[billcsho]

I think I have answered you in another thread.

 

[bonodo]

dude...seriously

or remote controls

 

[billcsho]

Yes, you can place 2 remote controls at any distance, but the signal may be too weak at a long distance (>20ft) since it has only a single IR LED emitter in it.