Title:
INFORMATION TRANSMITTING SYSTEM
Document Type and Number:
Japanese Patent JPS547211
Kind Code:
A
Abstract:
PURPOSE: To secure an economical information transmission of the trunk call from the originating register by inverting the polarity between A and B lines against the line unit in the public telephone circuit.
Inventors:
FURUYA TSUNEO
Application Number:
JP7206777A
Publication Date:
January 19, 1979
Filing Date:
June 20, 1977
Export Citation:
Assignee:
HITACHI LTD
International Classes:
H04Q1/30; H04Q1/38; H04Q3/42; (IPC1-7): H04Q1/30; H04Q3/42
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