IMPROVEMENTS IN OR RELATING TO THE INTERROGATION OF REMOTE STATIONS

摘要

An apparatus for reading remote sources of information, such as meters, is located at a remote station and is operated by interrogation signals transmitted via a telephone line from an interrogator at a local exchange. The apparatus includes a primary route selector and secondary route selectors connected to respective outputs of the primary route selector. Each secondary route selector has a plurality of outputs, to each of which at least one meter reading circuit is connected. The primary route selector detects a first interrogation signal, coded with information representing a predetermined secondary route selector, and provides an electrical path to that secondary selector for subsequent signals. A second interrogation signal is applied to the predetermined secondary selector to provide an electrical path for subsequent signals to a predetermined output thereof. Finally, a predetermined reading circuit, connected to the predetermined output of the secondary selector and represented by coded information in a third interrogation signal, reads the associated meter and transmits the reading back to the local exchange.