Patent search ap:("BELL TELEPHONE LABOR INC") AND inv:"CUSHMAN ROBERT W" Page 1

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发明授权
Volume control system 失效

公开(公告)号：US2035263A

公开(公告)日：1936-03-24

申请号：US67296433

申请日：1933-05-26

Applicant: BELL TELEPHONE LABOR INC

Inventor： CUSHMAN ROBERT W , HILL HENRY E

IPC: H03G7/00 , H03G7/02 , H04B1/64

CPC classification number: H04B1/64 , H03G7/004 , H03G7/02

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