04415774 is referenced by 53 patents and cites 3 patents.

An automatic answering device controlled by attached data equipment and used with a modem powered from the telephone line. The modem and automatic answering device are automatically connected to and subsequently powered by the telephone line when a ring signal has occurred on the telephone line and the data equipment has indicated that it is ready to receive data. The energy needed to connect the modem to the telephone line is slowly accumulated from a data equipment over a period of time prior to the connection of the modem to the telephone line. The modem automatically hangs up when the local data equipment signals disconnect or the modem at the other end of the telephone line disconnects.

Title
Line powered modem automatic answer device powered from equipment
Application Number
6/324842
Publication Number
4415774
Application Date
November 25, 1981
Publication Date
November 15, 1983
Inventor
R Byron Driver
Huntsville
AL, US
Agent
Weingarten Schurgin Gagnebin & Hayes
Assignee
Universal Data Systems
AL, US
IPC
H04M 11/00
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