TomGeorge:
Hi,You don't have anyone experienced in electronics at your work place?outsider's circuit is what I was leading you, too.
A step at a time so you would understand and learn what is going on.
You haven't answered post #15 yet, to really establish if the output is 24V high output.
Please read the references I have posted so you understand how to drive LEDs.Tom...
Hi. Looking at outsider's circuit and reading the link posted by you, I now understand my mistake.
Regarding post #15, the output voltage was indeed 24V as guessed by outsider. So, with whatever knowledge I had in electronics, I just kept on adding 10K resistors in series to bring the voltage down to the range of arduino.
I thought I would learn basic electronics while working with arduino. But, it seems as if I had a completely wrong approach. I think I should go through basic electronics first before moving anywhere ahead with the arduino, or I might damage the arduino or my laptop or even worse myself.
Thank you Tom and outsider.