For Kal

OK. I have hit into a snag. After seeing the original item, I have doubts as how its going to be lit with just a 1.5volt battery. Perhaps there is something missing here. The problem is this:

Let's say each LED takes 0.025A or current and since there are five LEDs in there, wired in parallel, the total current consumed would be 0.1A. And by my calculations, I don't even need a current limiting resistor to do anything. Either that or the 1.5 volt battery I have is exhausted. Man, sometimes I really want to kick myself for not getting that RM400.00 adjustable power supply. But that's another story.

Anyway, once its ready, I wll give you a shout and let you try. Unfortunately, I had to use thicker cables since the more flexible thinner cables were being sold for about RM35 per roll (instead of per meter) and this would mean RM70 down the drain. But don't go connecting the green LEDs yet, OK?

OK, this is the original circuit and if I slot in a normal
1.5volt "N" sized battery (a half-sized AA battery la)
the LEDs were so dim, even you could barely see the
glow. But using a multimeter to pump in 15mA, the
LEDs were glowing moderately bright. So, this means
the "N" seized 1.5 volt battery or any other 1.5 volt
batteries cannot be used since the red LEDs needs a
minimum of 1.82 volts (or so) to light up.

I tried with the new circuit and the result was the same.
I even put in a 1 ohm current limiting resistor bit it still
glowed like a sick LED. Oh, don't get me wrong but
these red LEDs do glow brighter than the original
ones given to me. And so, in conclusion..........

The small battery holder might have been meant for a
12volt 23 (whopping) Ampere battery, the same ones
you use for your car alarm remote. Doing some rough
calculations, 100Ohm resistor would do the job but as
the red LEDs are very bright, I upped the resistance
to 470Ohms, which more or less still gave the LEDs a
nice little glow. How it will affect the green LEDs, well,
we will have to use another set of resistors after all.
Aha! This will certainly throw out all the available
cramped space in there out of the window, of course.
But in the long run, perhaps an actual designed PCB
circuit board might do the trick.

[Update 30062009]
I just found some green LEDs and connected to the whole circuit. Using the initial 470Ohm resistor, the green LEDs were quite dim. So, I reverted back to using the 100Ohm instead and everything looks fine but I worry about the red LEDs being a bit too bright.