CH592994A5CH407275ACH407275ACH592994A5CH 592994 A5CH592994 A5CH 592994A5CH 407275 ACH407275 ACH 407275ACH 407275 ACH407275 ACH 407275ACH 592994 A5CH592994 A5CH 592994A5
Authority
CH
Switzerland
Application number
CH407275A
Original Assignee
Cit Alcatel
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Cit AlcatelfiledCriticalCit Alcatel
Publication of CH592994A5publicationCriticalpatent/CH592994A5/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)
Digital Transmission Methods That Use Modulated Carrier Waves
(AREA)