General Information

Serial #

N/A

Part Number

1

Total Parts

1

AKA

N/A

Patents

N/A

General Description

Metal and synthetic component parts.

Dimensions

Note: These reflect the general size for storage and are not necessarily representative of the object's true dimensions.

Length

61.0 cm

Width

66.0 cm

Height

209.0 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Communications

Category

Telephony

Sub-Category

N/A

Manufacturer

AKA

NORTHERN TELECOM

Country

Canada

State/Province

Unknown

City

Unknown

Context

Country

Canada

State/Province

Ontario

Period

TBM introduced in 1990, and discontinued in 2001. Dates of usage for this specific example are unknown.

Canada

Major component in Northern Telecom's "FiberWorld" product line, announced in 1989. A Canadian-based company, Northern Telecom/Nortel Networks was one of the most important manufacturers of telecommunications equipment in the world during the 1990s. This specific unit was used by Nortel Networks personnel for testing and product development purposes. (ref. 1)

Function

To convert electrical signals into an optical signal and combine them on a high capacity optical fibre.

Technical

Northern Telecom S/DMS products conform to the Synchronous Optical Network (SONET) standard established by North American telecommunications carriers in 1989. SONET defines data rates and formats, and optical signal parameters so that network components supplied by various vendors and used by various operators can interconnect. It is based on synchronous multiplexing,whereby several separate signals are combined on a single fibre by assigning each a recurring time slot in a bit stream. The type of data, or payload, is irrelevant to the operation of the system, meaning that everything from voice to video signals may be combined on a single fibre. The Transport Bandwidth Manager (TBM) provided high capacity inter-office and long-haul transport facilities at OC-3 data rates of 155.52 Mb/s. Input to system was in the form of electrical signals from the line trunk controller (LTC) of a DMS-100 central office switch. These signals operated at 1.544 Mb/s, the equivalent of 24 telephone lines. The TBM multiplexed 84 of these into an OC-3 for transport down a fibre at 155.52 Mb/s. The TBM thus acted as the interface between relatively low capacity electrical trunk lines and, for the time, high capacity optical channels. (ref. 1)

Area Notes

Unknown

Details

Markings

Components, controls, etc. labelled. Most components bear bar-coded labels. Dominant markings on unit include "TBE 00", "TBM 00". "TBM 01", and "DO 1" on top, front; "CMR/ OLSC/ J/ 01" in upper left front. Large decal in lower right front reads "NORTEL/ NORTHERN TELECOM/ Input Power:/ -48VDC/ 50 Amp/ [CSA logo]/ LR63680/ [UL logo]/ Telecommunications/ Equipment/ Listed 94N9/ Northern Telecom Limited/ St. Laurent, Quebec, Canada". Second decal, below, reads "NT7E78GC/ REL 01/ 29/99 ". Decal in lower left front reads "To be installed only in/ restricted areas in/ accordance with articles/ 110-16, 110-17, and 110-18 of/ the National Electrical Code,/ ANSI/NFPA No. 70".

Missing

Unknown. According to curator, this unit is inoperable. (ref. 1)

Finish

Dark grey painted metal rack has light grey synthetic fittings on one side; goldtone metal panels on reverse. Red, white and grey synthetic coverings on cables. Two red synthetic cone-shaped fittings mounted on top of unit.

Decoration

N/A