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Filing date
Publication date
Application filedfiledCritical
Priority to AU59138/73ApriorityCriticalpatent/AU480006B2/en
Priority claimed from AU59138/73Aexternal-prioritypatent/AU480006B2/en
Application grantedgrantedCritical
Publication of AU480006B2publicationCriticalpatent/AU480006B2/en
Publication of AU480006ApublicationCriticalpatent/AU480006A/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
H04Q1/457—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling with conversion of multifrequency signals into digital signals
H04Q1/4575—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling with conversion of multifrequency signals into digital signals which are transmitted in digital form
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Engineering & Computer Science
(AREA)
Computer Networks & Wireless Communication
(AREA)
AU59138/73A1972-08-10Method and apparatus for detecting the presence of signal components of predetermined frequency ina multifrequency signal
ExpiredAU480006B2
(en)
