Donald W Mclaughlin

US Patent:

39314740, Jan 6, 1976

Filed:

Dec 30, 1974

Appl. No.:

5/537291

Inventors:

Donald W. McLaughlin - Bolingbrook IL
David Q. Lee - Chicago IL

Assignee:

GTE Automatic Electric Laboratories Incorporated - Northlake IL

International Classification:

H04Q 144

US Classification:

179 16AA

Abstract:

A precise tone injection circuit for injecting tone signals to a constant current junctor circuit in a two-wire balanced circuit. The tone injection circuit includes a pair of transistors operating as constant current sources feeding the respective ones of the two wires. A phase splitter amplifier couples a tone signal to the base electrodes of the transistors to change the current through their collector electrodes via the emitter circuits thereof at a rate and frequency of the tone signals at the base. Since a two-wire balanced circuit is used, and the injected signal currents to each wire are 180. degree. out-of-phase, in-phase signals, that is, noise and voltage fluctuations, are reduced or rejected.

US Patent:

42544971, Mar 3, 1981

Filed:

Aug 6, 1979

Appl. No.:

6/064202

Inventors:

Tim Funderburk - Villa Park IL
Donald W. McLaughlin - Naperville IL

Assignee:

GTE Automatic Electric Laboratories, Inc. - Northlake IL

International Classification:

H04J 302
H04M 356

US Classification:

370 62

Abstract:

An improved conference circuit for use in a Pulse Code Modulation telephone switching system wherein a number of channels are combined so that a number of subscribers may participate in a common telephone conversation. The conference circuit is provided with a voice level coding arrangement whereby the voice level comparisons used in the speaker selection process are facilitated.

US Patent:

40073386, Feb 8, 1977

Filed:

Sep 18, 1975

Appl. No.:

5/614407

Inventors:

Donald W. McLaughlin - Bolingbrook IL

Assignee:

GTE Automatic Electric Laboratories Incorporated - Northlake IL

International Classification:

H04M 356

US Classification:

179 18BC

Abstract:

Most PCM systems provide non-blocking switching, with a channel per each terminal equipment being provided. In other words, they are dedicated channel arrangements. The present invention relates to PCM system using a method and arrangement which is a condensation of the required channels provided to time division switching by distribution of the channels instead of the usual dedicated channel method. In this system, a channel memory is created and provided to provide for control of which terminal equipments are allotted which channels (on a per call basis).

US Patent:

41752155, Nov 20, 1979

Filed:

Dec 5, 1977

Appl. No.:

5/857168

Inventors:

Donald W. McLaughlin - Naperville IL
Gerald F. Fetterer - Mount Prospect IL

Assignee:

GTE Automatic Electric Laboratories Incorporated - Northlake IL

International Classification:

H04M 356

US Classification:

179 18BC

Abstract:

An improved conference technique whereby a number of channels in a telephone switching system employing pulse code modulation for transmission purposes are combined so that a number of subscribers may participate in a common telephone conversation. The conference circuit is provided with a continuous threshold to pass the primary signal and to exclude the reflection. It is only used in the selection process, and for conditions which do not provide the threshold being met, the previous speaker is retained.

US Patent:

41267664, Nov 21, 1978

Filed:

Dec 5, 1977

Appl. No.:

5/857165

Inventors:

Donald W. McLaughlin - Naperville IL
Gerald F. Fetterer - Mount Prospect IL

Assignee:

GTE Automatic Electric Laboratories Incorporated - Northlake IL

International Classification:

H04M 356

US Classification:

179 18BC

Abstract:

An improved conference technique whereby a number of channels in a telephone switching system employing pulse code modulation for transmission purposes are combined so that a number of subscribers may participate in a common telephone conversation. The conference circuit is provided with a continuous threshold to pass the primary signal and to exclude the reflection. It is only used in the selection process, and for conditions which do not provide the threshold being met, the previous speaker is retained.

US Patent:

40229815, May 10, 1977

Filed:

Jul 28, 1976

Appl. No.:

5/709580

Inventors:

Donald W. McLaughlin - Bolingbrook IL
David Q. Lee - Chicago IL

Assignee:

GTE Automatic Electric Laboratories Incorporated - Northlake IL

International Classification:

H04M 356

US Classification:

179 18BC

Abstract:

A method of providing a multi-port conference circuit for use in a telephone switching system employing pulse coded modulated signals for transmission and supervision. Samplings of coded information are employed as a source of conference data and comparison with the digital information contained therein is employed to choose the speaker in a conference group.

US Patent:

43084729, Dec 29, 1981

Filed:

Dec 3, 1979

Appl. No.:

6/099948

Inventors:

Donald W. McLaughlin - Naperville IL

Assignee:

GTE Automatic Electric Labs Inc. - Northlake IL

International Classification:

H03K 5135
H03K 514
H03K 526

US Classification:

307518

Abstract:

An apparatus adapted to check for the continuous presence of an incoming clock pulse train comprising an exclusive OR gate, to the input of which are coupled the clock pulse train and a second train of clock pulses delayed by one half the period of the incoming clock pulse train. A third train of clock pulses delayed by three quarters of the clock period is utilized to strobe the OR gate output into a pair of flip-flops. If the two inputs to the OR gate are the same a fault exists and a flip-flop is set to indicate on which excursion the fault occurred.

US Patent:

42018935, May 6, 1980

Filed:

Sep 28, 1978

Appl. No.:

5/946699

Inventors:

Donald W. McLaughlin - Naperville IL

Assignee:

GTE Automatic Electric Laboratories Incorporated - Northlake IL

International Classification:

H04Q 1104

US Classification:

370 58

Abstract:

Groups of analog trunks are shown connected to analog to digital converters. The converters are each assigned a time during which their associated trunks may access a common data bus to the pulse code time division switching system. Provision is made for the use of T1 carrier channels to utilize the times normally assigned for the analog trunks by the provision of a circuit that one excludes the other from accessing the bus.