lol, thanks robodude, anyway, so theres the information, and i plugged it into the link Beth gave me and it came up with 5 rows of 3 LEDs each, with a 100 ohm resistor at the end of each one 
(running at 25 mA)
well, off to the mall to fill my Simon mall gift card that doubles as a Visa 
, cya later
[size=59]Edited for spelling errors[/size]
Sure thing… But how you get 5 x 3 array? Thats 15… You have 60LEDs, no?
15 x 4 = 60
Oh woops 
He wants 15 LEDs per PCB! I didn’t notice that. sorry! :oops::oops:
yup, seamus got it correct, i will have 4 LED…towers/lines that will make night day
I didn’t get from his post that he didn’t know, or couldn’t get the specs. 
happily, the LEDs and resistors will be getting here either tomorrow or wednesday
All I’m gonna say is 15x 18,000mcd LEDs operating in the IR range may be dangerous to your eyes so please exercise caution when handling these.
I second that cautionary note! The visible multi-thousand mcd LEDs are downright painful to look into.
i am not getting the IR LEDs for right now, just normal white 18,000 mcd LEDs and thank for the advice about the IR LEDs, i iwll be sure not to have too many and i will try and keep them sub 8-10 thousand mcd
Ah, well, at least with white LEDs you’ll know you are doing damage when you stare into them. 
Oh and actually white explains the 3.3v forward voltage as well.
lol
stares into LEDs…ouch eyes bleed
why, do speccific colors have specific voltages? 
Different types of LEDs have different operating voltages, based on the semiconductor chemistry and method used to produce the light.
lol 
well, guys, quick update on the LEDs, got a breaboard today and set up wat 1 of the turrents/bar lights will look like on my rover, took some before and after pictures in the dark, its not too impressive, but i think it will be ok
img2.putfile.com/thumb/6/16122523779.jpg
img2.putfile.com/thumb/6/16122523747.jpg
well, what do u think , not bery bright eh? my eyes kinda bled/melted wen i first turned them on
thats 15 LEDs, im going to have 60 on the rover
That’s going to be bright!!! 
Chunga, my eyes are bleeding just looking at a photo!
What would you consider a good mcd for a LED that will illuminate a sheet of transparent acrylic/lexan?
yes, i think it would be plenty birght lol
Chunga,
LEDs function quite differently from most other components we encounter in the robot electronics world. Instead of being fed with a constant voltage, they need to be fed with a constant current. When your getting started with electronics (and I say that without any sense that I really have any meaningful handle on it all yet) its easy to see these things as being fundamentally different. But they are not necessarily. The resistor driving the LED technique is about taking a known constant voltage and dividing it down to a known constant current.
How all this answers your original question, well… it doesn’t at all. It just seemed that you were struggling with a concept that took me longer than it should have to learn and I wanted to share
Im using IR LED’s. na naw na naw na
