In ultrasound, "knobology" refers to the essential knowledge and use of the machine's controls (knobs, buttons, dials, sliders) to optimize image quality, select transducers, adjust settings like depth, power, overall gain, TGC, Doppler controls, etc.
It's the practical understanding of how to fine tune our settings in order to produce the highest quality images possible.
To be a good sonographer, you MUST have a solid understanding of all the knobology. It's technology...and we are technologists