General Information

Serial #

24979

Part Number

1

Total Parts

2

AKA

Level recorder

Patents

N/A

General Description

wood casing/ metal component casings & parts, hardware/ synthetic parts/ paper chart

Dimensions

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

Length

58.0 cm

Width

31.0 cm

Height

23.0 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Communications

Category

Service-test equipment

Sub-Category

N/A

Manufacturer

AKA

Bruel Kjaer

Country

Denmark

State/Province

Unknown

City

Copenhagen

Context

Country

Canada

State/Province

Ontario

Period

late 1950s+

Canada

A piece of equipment used at a Canadian manufacturing facility. The donor's father was Roland Ouellette who worked as an electronics technician at the CIP mill in Hawkesbury, Ontario. He was self taught in electronics but still received 4 patents for his inventions. Canadian Patents: # 925285 issued May 1, 1973; class 33-176; # 925286 issued May 1, 1973;  class 33-179; # 1222319 issued May 26, 1987;  class 354-29. United States Patent: #4,644,174 issued Feb 17, 1987.

Function

A high speed recording instrument used for the measurement of reverberation time, noise level, and the frequency response of microphones and loudspeakers. This example was used in a pulp mill, in the electronics shop for maintenance purposes.

Technical

Brüel & Kjaer were makers of high fidelity audio equipment and became more familiar as B&K in the 1980s; the firm is still producing test equipment though not of as high standard as this item. B&K instruments like this one were probably only used in really well equipped labs because of their cost. The quality of the workmanship is A1 almost to the point of excess. The instrument has a built in potentiometer and strip chart recorder with modules to control each. The frequency range is 20 - 400 c/s (Hz) and the lower limit could be adjusted over this range. The writing speed range of the recorder is 50-1000 mm / sec.

Area Notes

Unknown

Details

Markings

label on back reads "Type/ 2304/ Serial/ 24979/ Bruel & Kjar/ Copenhagen"/ white lettering on back reads "Made in Denmark"/ black lettering on component casings for control functions & reading "Bruel & Kjar/ Copenhagen", "Level Recorder Type 2304" & "50 db/ Potentiometer Type 2347"

Missing

appears complete

Finish

casing stained brown & coated/ glossy green painted component casings/ glossy black painted parts/ black controls/ metallic parts/ white paper with black backing

Decoration

N/A