Abstract: An encoding switch generates selected patterns of voltage signals that correspond to the binary bits of a code word. A base of the switch supports a plurality of pairs of terminals. Each pair of terminals includes a conducting stationary terminal and a conducting moveable terminal that is positioned adjacent to the stationary terminal. An encoding module is inserted over the base to define a particular pattern of voltage signals. The module has a plurality of selectively detachable tabs that engage the movable terminals and press the terminals against adjacent stationary terminals when the module is slidingly engaged with the body. Relatively long tabs of the module establish connections corresponding to the data bits of a word and at least one short tab establishes a power connection for the switch.