Frederick Electronics Corporation

John W Spaniol

Marvin K Perlman

John J Bowerman

Ronald E Tollum

Jack L Woodell

John F Wilson

Larry C Bieber

Julius A Barthelme

Edward D Hoover

William A Moshier

Philip K Hammond

A teletypewriter line keyer with a switching current regulator responsive to a floating, loop current powered voltage comparator used as a loop current monitor. The line keyer, which may have positive and negative line current keying, uses a single current monitor to control positive and negative current regulators responsive to the positive and negative keying respectively. The switching regulators operate within a relatively narrow band centered around the nominal signaling current, with filtering being provided for ripple control. The circuit may also include a keying detector and open loop detector for system monitoring.

Teletypewriter line keyer with switching current regulator

A distributed processing telex switch having different levels of processor control to handle the calls between terminations connected to the exchange is disclosed. A common control processor occupies the highest level of processor control and function as the system-wide manager. Next below common control is a plurality of master control processors which function to switch the command data between common control and the lower levels of processor control, and to handle the conversation data generated by each of the terminations connected to the exchange. Each master control processor controls a predetermined number of termination from among all of the terminations connected to the exchange. Connected to each master control processor is a plurality of group control processors which control the flow of data to and from a second predetermined number of terminations from among the terminations controlled by each master control processor. The group control processors occupy the next lower level of processor control from the master control level. Associated with each group control processor is a line control processor that cooperates with its associated group control processors to produce the signaling sequences in the terminations and to handle the conversation data from and to the terminations. The line control processor occupy the lowest level of processor control.

Distributed processing telex exchange

A circuit for the systematic handling of conversation data from a calling party to a called party for use in a distributed processing telex exchange is disclosed. The customer terminations connected to the exchange are divided into a predetermined number of groups of terminations having a predetermined number of terminations in each group. Associated with each group of terminations is a frame memory which has memory capacity for storing a single bit of conversation data from every termination connected to the exchange. Associated with each frame memory is a vector memory which has a memory location associated with each termination in a group. Each vector memory location contains a frame memory address that addresses the location in frame memory containing the conversation data to be forwarded down to the termination associated with the current vector memory address. In addition, each vector memory location contains an active bit which is included with the conversation data forwarded to the called party termination to indicate that a call is in progress for that termination.

Circuit for handling conversation data in a distributed processing telex

Growing community of inventors

Studio City, CA, United States of America

John W Spaniol