Patent search ap:("BELL TELEPHONE LABOR INC") AND inv:"GORDON JR MALCOLM K" Page 1

1.

发明授权
Amplifying system 失效

公开(公告)号：US2031919A

公开(公告)日：1936-02-25

申请号：US53275431

申请日：1931-04-25

Applicant: BELL TELEPHONE LABOR INC

Inventor： BENNETT ARTHUR F , GORDON JR MALCOLM K

IPC: G04D7/06 , H03F13/00

CPC classification number: H03F13/00 , G04D7/06

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