[Robin Reiter] had a powered TV stand that only rotates around 20°, because who really needs their TV to rotate fully? He wanted to turn it into a motorized turntable for shooting videos, but first he had to hack it.
After opening it up [Robin] discovered that there was a surprising amount of electronics in the base. In addition to a DC motor, there was a potentiometer attached to a gear to give feedback, but it was set up for partial rotation so it had to be yanked out.
There was also a plastic gear with teeth around just part of the interior. [Robin] took a picture of the gear and dropped it into Fusion360, using the photo as a reference image while he re-created the gear. The new piece had teeth all around the periphery. After printing it out he glued it into the old gearbox, and now he had turned his TV stand into a motorized turntable.