Abstract: A remote switch system for controlling electrical devices, such as electrical lights, from a remote switch location using a single optical fiber to communicate the controlling signal from the remote switch to the device. Typically, the remote switch may be added to a normal switch near the device during modification or remodeling of a building, automobile or the like or installed in during original construction. The fiber optic system includes both an emitter and a detector at the first end of a fiber optic. The emitter sends a light signal through the fiber and the detector detects a reflected signal coming back through the fiber. Conventional switching circuits or relays turn the electrical device, e.g. a light, to a different state, such as "on" or "off" in response to a pulse of light or the presence or absence of a returning signal.