A locking knob has a mounting base and a knob. The mounting base is shaped to be mounted to a fixed base of an electronic device, and includes a knob receiver extending upwardly to form a knob receiving portion. The knob has a knob top that is adapted to be grasped for manipulating the knob. The knob is positioned in the knob receiving portion of the knob receiver to operably engage a shaft of the electronic device so that the knob can be used to turn the shaft. A position selection mechanism enables locking the knob in either a lowered position or a raised position, and a locking feature of the knob interlocks with the locking base when the knob is in the lowered position, but leaves the knob free to rotate when in the raised position.