Northern Telecom Limited

Michael J Coleman

Adrianus P Van Gaal

Joseph J Lommen

Frederick Caldwell Livermore

Colin Donald Smith

James E Anderson

Brian T Osborne

Remo Contardo

Robert C Dittburner

Peter J Kielstra

Nicholas J Pitt

A telecommunications shelf module is provided having electronic circuit packs and conductors extending from the circuit packs to an interface station for connection to conductors exterior of the pack, the module detachably mountable in a frame. The module preferably has a cooling arrangement included in its structure.

Telecommunications equipment

Electronic circuit pack and mounting frame combination in which a mating connector joined to conductors coming in for connection to the circuit pack, is held within a connector holder for protection and connection purposes. Straight line action of the connector holder is ensured to ensure proper alignment of the mating connector with the circuit pack connector. It is preferable for the connector holder to be permanently attached to the frame to support the weight of the holder and minimize strain upon the incoming conductors.

Electronic circuit pack and mounting frame combination

An overvoltage protection device, for protecting communications equipment against hazardous voltages cue to lightning or power surges, comprises a primary protector, for example a gas tube device, and a back-up protector connected in parallel. The back-up protector includes a semiconductor pn junction, and is preferably a pair of diodes back-to-back. The back-up protector has a breakdown voltage slightly higher than that of the primary protector and is arranged to fail short-circuit once it has operated so as to provide an indication that the primary protector failed to operate.

Overvoltage protection device

Growing community of inventors

Woodlawn, Canada

Michael J Coleman