Modem coupler for multi-line key telephone system

Claim 1

A self-sufficient modem coupler making it possible for a modem coupled to a digital data processing terminal to access a key service unit of an analog telephone communication system directly from a multi-line key telephone set having a set cord terminating in a plug that is normally inserted in a station jack to connect the set to the key service unit of the system, said modem coupler being provided with ring, tip and at least one pair of data terminals and comprising: (a) a coupler cord for connecting the modem coupler to the modem; (b) a phone jack to receive the plug of the telephone set for connecting the set to the coupler; (c) a line jack to receive a line cord to connect the terminals of the coupler to the station jack, whereby the coupler is then connected to corresponding terminals in the key service unit; and (d) a double-pole, double-throw switch having one operative position that puts the modem coupler in a voice communication mode and in another operative position, puts the modem coupler in a data communication mode, said switch in said one position connecting the multi-line telephone set to said station jack and in doing so connects said set to said key service unit, said switch in said other position connecting said modem to said station jack and in doing so giving the modem access to an outside line.