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Publication of BE693127ApublicationCriticalpatent/BE693127A/xx
H04Q1/00—Details of selecting apparatus or arrangements
H04Q1/18—Electrical details
H04Q1/30—Signalling arrangements; Manipulation of signalling currents
H04Q1/44—Signalling arrangements; Manipulation of signalling currents using alternate current
H04Q1/444—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies
H04Q1/45—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling
H04Q1/453—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling in which m-out-of-n signalling frequencies are transmitted
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Engineering & Computer Science
(AREA)
Computer Networks & Wireless Communication
(AREA)
Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo
(AREA)
Devices For Supply Of Signal Current
(AREA)
Use Of Switch Circuits For Exchanges And Methods Of Control Of Multiplex Exchanges
(AREA)