What you need to know to get started

1. The mode (specific scale) is the melodic framework of a raga and defines the frequencies (notes) that are used in it. 

2. The Sa is the starting frequency, the fundamental or dominant note, the other note frequencies are divisions established on a scale of 12 notes starting from the Sa (fundamental note) to the upper Sa octave.The tanpura (drone) indicates the dominant (the Sa). 

3. In Indian classical music, there is no mixing of modes. The raga played comes to life in the prelude and unfolds in infinite variations within the framework of the frequencies And rules that define it.

On Indian music notation :

Notes are written with upper and lower case letters. Uppercase letters refer to the so-called "natural" (Shud) notes ; Lower case letters refer to "diminished" notes, (Komal) below their natural value (Only one note is increased, above its natural value, it is the Ma tivra which is written Ma+ ).