Manual pulse generator

A manual pulse generator (MPG) is a device for generating electrical pulses (short bursts of low current) in electronic systems under the control of a human operator (manually), as opposed to the pulses automatically generated by [software]]. MPGs are used on computer numerically controlled (CNC) machine tools, on some microscopes, and on other devices that use precise component positioning. A typical MPG consists of a rotating knob that generates pulses that are sent to an equipment controller. The controller will then move the piece of equipment a predetermined distance for each pulse.

For example, the handwheel of a typical CNC control will move any of the slides of the machine by one minimum increment, such as 1 micrometre or 1 ten thousandth of an inch, for each pulse, and the handwheel will give one haptic click to confirm to the user that a single increment occurred. Several selector switches control the handwheel's output: one allows each of the machine's axes (X, Y, Z, and so on) to be selected in turn; another shifts through several ranges of output, so that one click of the wheel is either one minimum increment, 10 times that, or 100 times that.