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.)
Publication of BE634529ApublicationCriticalpatent/BE634529A/de
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
Anordnung zur Erfassung von auf mehreren Signalleitungen in wahlloser Folge einlaufenden Signalimpulsen, insbesondere von Zählimpulsen in Fernsprechanlagen
Disconnecting device for phase-shift capacitors - has remote control responsive receiver with capacitor group, having input coupled to heavy current network
Elektronische Schutzeinrichtung zur selektiven Erfassung von Dauererdschlüssen und Erdschlusswischern in Netzen mit nicht wirksam geerdeten Sternpunkten