I’ll preface this by saying I’m NOT an experienced, long-time producer, and I’m pretty sketchy with theory, in general, as I’ve never been formally trained… Anyway, honestly, when you’re first learning music theory, and it’s for the purposes of creating electronic music, focus on the minor scale first, until you’re comfortable enough with that. I’d say that if you’re writing Dubstep, chances are you’re going to be writing pretty much EVERYTHING in the minor scale (I’m sure I’ll get reamed for making that claim haha).
A good (meaning “easy” place to start would be A minor. Your basic Amin scale is just all of the white keys (Keys in the scale of your root shouldn’t feel out of place- or wrong- typically (again, I’m sure a theory guru will be here to destroy me any minute now lol). For chords in minor, find whatever key you want the track to be in (say F#…). Right, so locate a F# key on your keyboard- next, starting on the NEXT key after your root note (G in this case), count UP 3 half-steps- (so F# = root, UP 3 half-steps would go “G”, “G#”, “A”- so A is your next note to remember. Then, from A, where you left off, continue counting UP to the 7th half-step from the root note-- so “A” was the third…“A#”, “B”, “C”, and “C#” will get you to the 7th half-step. S
So, for your root note F#, your most basic minor chord will be F# - A - C# (in other words, basic minor chord = 1, 3, 7 – 1 is your root note, 3 half-steps up for the second note, and 7 total half-steps up for the third note, to get a basic 3-note chord). There are much more complex versions of just the F#m chord when you get into melodic minor, harmonic minor, pentatonic minor, etc.
Apologies if this is no help, or too confusing the way I typed it, I’m half asleep, and already don’t know what the hell I’m talking about to begin with
random site with music theory/scales & chords info