Arunk has quite an extensive writeup on Ragas and Scales (Part 2).  There is also a Ragas and Scales (Part 1).  I have not read through both of them, yet.  After that comes understanding, assimilation and all that stuff.  Too much work on my part 😦

So, my idea is to just listen to Carnatic and leave all that analysis stuff out for those that can figure it out.  I plan to stick to that idea.