General Information

Serial #

N/A

Part Number

1

Total Parts

1

AKA

N/A

Patents

N/A

General Description

Metal casing and connector pieces with hard synthetic knobs and a flexible synthetic power cord covering and handle.

Dimensions

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

Length

23.3 cm

Width

21.0 cm

Height

14.2 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Communications

Category

Sound

Sub-Category

N/A

Manufacturer

AKA

Bruel Kjaer

Country

Denmark

State/Province

Unknown

City

Unknown

Context

Country

Canada

State/Province

Ontario

Period

1981-1998

Canada

Bell Northern Research, was the research and development subsidiary of Northern Telecom (later Nortel Networks) and Bell Canada. It was built by Northern Telecom at its Trans-Canada plant in Montreal. Northern Telecom and its predecessor, Northern Electric, was for decades Canada’s largest manufacturer of telecommunications equipment. Originally a subsidiary of the AT&T-owned Western Electric, for which it manufactured American-designed products for the Canadian market, Northern Electric became Canadian-owned in the 1950s and in the 1960s began to design and produce equipment to meet the distinctive needs of Canadian telecommunication companies. In the 1970s, through its new research subsidiary, Bell Northern Research, the company made a concerted shift from conventional analogue equipment into the emerging field of digital communications, becoming in the 1980s the first equipment supplier to provide a complete line of fully digital switching and transmission gear. During this decade the company moved aggressively into export markets, and opened manufacturing and R&D operations in several countries. The company’s sales soared during the internet boom of the 1990s, but a combination of poor financial decisions and a failure to maintain its technological edge led eventually to its bankruptcy in 2009. The original Bell Northern facilities were designed with cutting edge telecommunications research and development in mind with the first three buildings on the campus featuring laboratories, an extensive research library, and an anechoic chamber. The anechoic chamber was the focal point of the Bell Northern Research acoustics research examining both the technology and placement of speakers and microphones in telecommunication devices. The anechoic chamber group was organized under the Industrial Design and working together with design were responsible for the development of the acoustic properties of most products. (From the Acquisition Proposal, see Ref. 1)

Function

Used to generate the sound pulse (sinusoidal waves) for acoustic experiments. (From the Acquisition Proposal, see Ref. 1)

Technical

Used in conjunction with other Bruel & Kjaer equipment to build an experimental acoustic apparatus. (From the Acquisition Proposal, see Ref. 1)

Area Notes

Unknown

Details

Markings

On the proper front: "Sound Power Source Type 4205/ Overload/ Battery/ Check On/ Off"/ Around the dials and switch on the proper front: "Sound Power Spectrum. Octave/ 125 Hz/ 250 Hz/ 500 Hz/ 1kHz/ 2 kHz/ 4 kHz/ 8 kHz/ Wide Band/ 100 Hz - 10 kHz/ Ext. Filter"/ "On/ Off"/ "Sound Power Level/ dB re.1 pW/ 50/ 60/ 70/ 80/ 90/ 0/ 1/ 2/ 3/ 4/ 5/ 6/ 7/ 8/ 9/ 10"/ On the stickers on the proper front: BNR [logo]/ ACOUSTIC DESIGN"/ "Bell-Northern Research/ L0021079"/ "nt/ FOR/ INDICATION/ ONLY"/ On the proper back panel: "Power Supply/ Type 2808/ Output/ Power/ Off/ Charge/ On/ [logo]/ Made in/ Denmark/ 50-400Hz/ Int/ Ext./ + 6,6 V - +15 V/ Charge + 12 V/ Remote Control/ Ext. Power Supply/ Ext. Filter/ From/ Output/ To/ Input/ White Noise/ 50 Hz/ - 10 kHz/ Sound Source/ HP 1001/ Sound Power Level Calibration/ Wide Band / and/ Ext. Filter/ 8 kHz/ 4 kHz/ 2 kHz/ 1 kHz/ 500 Hz/ 250 Hz/ 125 Hz/ CHARGE VOLTAGE MUST ONLY/ BE APPLIED WHEN USING/ RECHARGEABLE BATTERIES/ Made in Denmark/ Brüel & Kjaer/ Type/ 4205/ Serial No./ 918890/ Made in Denmark"/ On an off-white sticker on the proper back: "BLACK COMMON/ BLUE CHARGE/ RED EXT. POWER"/ On the sticker on the proper bottom: "[logo]/ BRUEL & KJAER CANADA LTD./ 90 Leacock Road, Pointe Claire, Qué./ MODEL 4205 S.N. 918890/ VOLT/ HZ/ VA/ PURCHASE/ DATE/ 9/22/81/ FUSE"/ Incised on the casing next to the sticker: "L21079"

Missing

Appears complete

Finish

Predominantly black casing with light green panels on the proper front and the proper back. On the green panels are black markings and knobs, silver coloured metal connectors, a white meter and white, pink and grey stickers. On the proper top there is a black synthetic handle that collapses almost flush with the top of the casing.

Decoration

N/A