General Information

Serial #

N/A

Part Number

6

Total Parts

6

AKA

N/A

Patents

N/A

General Description

Hard-bodied case to store a hydrophone along with its contents. Étui rigide pour entreposer un hydrophone ainsi que ses composantes.

Dimensions

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

Length

17.5 cm

Width

28.0 cm

Height

9.3 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Communications

Category

Sound

Sub-Category

N/A

Manufacturer

AKA

Beachell

Country

Canada

State/Province

Ontario

City

Ottawa

Context

Country

Canada

State/Province

Quebec

Period

Hydrophone was designed and built between 1970 and 1980. It was subsequently given by Chester Beachell to his niece as a gift in 1994. L'hydrophone a été conçu et construit entre 1970 et 1980. Il a ensuite été donné par Chester Beachell à sa nièce comme cadeau en 1994.

Canada

The hydrophone No. 20 is one of several hydrophones designed and built by Canadian Chester Beachell, at the NFB in Montreal, between 1970 and 1980. No. 20 is one of the two known surviving examples of Beachell hydrophones. Hydrophone No. 20 is believed to be the last hydrophone Beachell built and represents the culmination of his work developing improved technology for underwater listening and recording. Chester Beachell was a Senior Research Officer, Technical Research Division at the National Film Board from 1951 to 1980. He participated in many projects documenting research expeditions for the NFB. Beachell wrote that “the presence of all this sound in the ‘silent world’ convinced him that he should design and build high quality hydrophones, and a recorder, which could be carried by a diver”. He designed his first experimental hydrophone in November 1970 following a request from Bané Jovanovic, the director of NFB film The Sea. He continued to develop improved hydrophone technology, resulting in underwater recordings that were used in a number of films produced by the National Film Board of Canada.

Function

Used to store and protect the hydrophone and its contents when not in use. Utilisé pour entreposer et protéger l'hydrophone et ses composantes lorsqu'ils ne sont pas utilisés.

Technical

Early hydrophones were improved for military use, primarily for the purpose of locating submarines and icebergs. Hydrophone arrays, or large groups of hydrophones positioned thousands of miles apart, were also used for navigational purposes and in military tracking and contained pre-amplifiers to limit noise contamination. In addition to military purposes, hydrophones today are used to study marine life and assist in undersea conservation efforts. The ordinary elastic bands, bimorph crystal, and protective grill are indicative of Beachell’s early work and can be seen when looking at Hydrophone No. 20. It is likely made out of “hard duraluminum” which allowed Beachell’s hydrophones to withstand pressures of at least 45atm, a depth of 1500ft and was likely coated in Verithane to protect the silver coating from the salt water.

Area Notes

Unknown

Details

Markings

On the white adhesive label on the top surface of the case: " CHESTER . BEACHELL /. (...) EDMONTON, /. ALBERTA ". Painted on the top surface of the case: " BEACHELL /. MONTREAL " On the inside of the top surface of the case: " HYDROPHONE POWER SUPPLY NO. 20 /. 9 VOLT BATTERY REQUIRED OR, /. EXTERNAL 9 VOLT BATTERY, NEG. GND. On the front and side surface of the case: " HYDROPHONE & POWER SUPPLY NO. 20 /. 9 VOLT BAT. REQUIRED OR EXT. BAT. NEG. GND. /. 10 METRE CONNECTING CABLE & SILICONE GREASE "

Missing

Appears complete.

Finish

Hard-bodied brown wooden case. The case two metal hinges, two golden coloured metal clasps and a black leather handle. The outside surface of the case has numerous white adhesive labels with black text. The exterior of the case has some scratches due to wear and tear. Étui rigide brun en bois. L'étui a deux charnières en métal, deux fermoirs en métal en couleur d'or et une poignée noire en cuir. La surface extérieure de l'étui a plusieurs étiquettes adhésives blanches avec de l'écriture noire. L'extérieur de l'étui a des égratignures en raison d'usure normale.

Decoration

N/A