General Information

Serial #

N/A

Part Number

1

Total Parts

4

AKA

N/A

Patents

N/A

General Description

PLASTIC AND METAL CONSTRUCTION

Dimensions

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

Length

6.1 cm

Width

N/A

Height

N/A

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Communications

Category

Radio

Sub-Category

N/A

Manufacturer

AKA

RAYTHEON

Country

United States of America

State/Province

Massachusetts

City

Newton

Context

Country

Unknown

State/Province

Unknown

Period

Unknown

Canada

CK722 WAS 1ST TRANSISTOR SOLD TO GENERAL PUBLIC. IT IS A CONSUMER VERSION OF THE CK718, RAYTHEON'S FIRST JUNCTION TRANSISTOR, USED FOR AMPLIFICATION IN HEARING AIDS. IN THE 1950S MFG METHODS FOR SEMICONDUCTOR DEVICES WERE CRUDE, AND MANY TRANSISTORS FAILED QUALITY CONTROL TESTS. RATHER THAN DESTROYING CK718S THAT DID NOT MEET GAIN AND NOISE PERFORMANCE SPECS. FOR HEARING AIDS, RAYTHEON REBRANDED THEM FOR THE CONSUMER MARKET AS THE CK722 OR THE CK721. THE CK722 WAS MARKETED TO ELECTRONIC HOBBYISTS, WHO INCORPORATED IT IN HOMEMADE RADIO RECEIVERS, OSCILLATORS, SPEAKERPHONES & OTHER DEVICES. (REF. 2).

Function

ARE SEMICONDUCTOR PARTS

Technical

EXAMPLES OF VERY EARLY GERMANIUM JUNCTIONTRANSISTOR, WHICH WAS INVENTED BY WILLIAM SHOCKLEY IN 1951. CONSISTING OF 3 LAYERS OF DOPED SEMICONDUCTOR MATERIAL, IT PERFORMED THE SAME AMPLIFICATION AND OSCILLATION FUNCTIONS AS A VACUUM TUBE TRIODE. IN COMPARISON TO A VACUUM TUBE, THOUGH, THIS DEVICE WAS SMALL, CONSUMED MUCH LESS POWER, AND GENERATED MUCH LESS HEAT. (REF. 2).

Area Notes

Unknown

Details

Markings

'CK 722 Raytheon C-12' PRINTED ON CAP/ RED DOT APPEARS ON ONE SIDE OF CAP, NEAR BASE

Missing

NONE

Finish

BLACK CAPS HAVE CLEAR PLASTIC BASE/ 3 FINE SILVER WIRES EXTEND FROM BASE

Decoration

N/A