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Application filedfiledCritical
Priority to JP7197375ApriorityCriticalpatent/JPS51148304A/ja
Publication of JPS51148304ApublicationCriticalpatent/JPS51148304A/ja
Publication of JPS5528584B2publicationCriticalpatent/JPS5528584B2/ja
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
H04Q1/46—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies comprising means for distinguishing between a signalling current of predetermined frequency and a complex current containing that frequency, e.g. speech current
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Engineering & Computer Science
(AREA)
Computer Networks & Wireless Communication
(AREA)
JP7197375A1975-06-161975-06-16Circuit to discriminate speech signals and audible signals
GrantedJPS51148304A
(en)