Patent search ap:("BELL TELEPHONE LABOR INC") AND inv:"SMART BRAND" Page 1

1.

发明授权
Repeater system 失效
Title translation: 中继系统

公开(公告)号：US2110284A

公开(公告)日：1938-03-08

申请号：US9956436

申请日：1936-09-05

Applicant: BELL TELEPHONE LABOR INC

Inventor： BACHELET ALBERT E , SMART BRAND

IPC: H04H1/00 , H04H20/72 , H04H20/82 , H04H60/79

CPC classification number: H04H60/79 , H04H20/72 , H04H20/82

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