Change the velocity of the source relative to the observer:
Balmer Series: Adds lines of Balmer series corresponding to n=3
through n=7.
Paschen Series: Adds lines of Paschen series corresponding to n=4
through n=8.
Lyman Series: Adds lines of Lyman series corresponding to n=2
through n=6.
Brackett Series: Adds lines of Brackett series corresponding to
n=5 through n=8.
Positive Velocity indicates that the emitter moves TOWARD observer.
Negative Velocity indicates that the emitter moves AWAY from observer.