Where does LFO PW 1+2 gets its source

[fsx]

Hello!

Sorry if I am bombing with questions (and I suppose I will continue even if I have RTFM...) but I cannot find where LFO PW 1+2 gets its source.
I mean, it constantly changes (when the pulse wave is selected) to modulate, but (without using ASSIGN) it seems it cannot be controlled in a discrete time frame.


EDIT: Ok I have found how it works... actually LFO1 controls it and the amount is set to oscillate through the 0 (zero) of the LFO and move to the extreme + and - altering the pulse width. That's why it seems differently related to the LFO, because it is! =)