Abstract: An apparatus and method for remotely answering a door. The apparatus includes a switch, a telephone transmitter and an a telephone receiver positioned near the door. At least one telephone station is operable to place a telephone call to a remote telephone identified by a pre-determined telephone number. An interface detects actuation of the switch and signals the telephone station to place the telephone call in response to actuation of the switch and places the telephone transmitter and receiver in communication with the telephone to establish telephonic communication between the telephone transmitter and receiver and the remote telephone.

Abstract: An apparatus for muting communications subscriber equipment connected to a communications line includes a monitoring circuit for monitoring electrical conditions of the communications line, when the subscriber equipment is connected thereto. A disconnection circuit is provided for disconnecting the subscriber equipment from the communication line and a termination circuit is provided for terminating the communications line with a dummy termination when the subscriber equipment is disconnected, such that, the communications line appears to be terminated by the subscriber equipment. When the subscriber equipment is disconnected from the communications line a power supply circuit provides power to the subscriber equipment with the same electrical conditions as determined by the monitoring circuit prior to disconnecting the subscriber equipment.

Abstract: A circuit for use with a SCWID adjunct to remove A.C. in-band signaling tones from the voice path to a telephone apparatus serially connected to the adjunct. The A.C. signal component is carried on top of the D.C. voltage used to power the telephone. The circuit includes means to monitor the D.C. voltage level and to pass this voltage substantially unchanged to the telephone. The A.C. signal in the form of a FSK tone, received from the central office, is used by the adjunct to provide a subscriber with call feature information such as the identity of a calling party while the telephone is off-hook.