CH567850A5CH9473ACH9473ACH567850A5CH 567850 A5CH567850 A5CH 567850A5CH 9473 ACH9473 ACH 9473ACH 9473 ACH9473 ACH 9473ACH 567850 A5CH567850 A5CH 567850A5
Authority
CH
Switzerland
Application number
CH9473A
Original Assignee
Int Standard Electric Corp
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 Int Standard Electric CorpfiledCriticalInt Standard Electric Corp
Publication of CH567850A5publicationCriticalpatent/CH567850A5/xx
H04Q1/00—Details of selecting apparatus or arrangements
H04Q1/18—Electrical details
H04Q1/30—Signalling arrangements; Manipulation of signalling currents
H04Q1/38—Signalling arrangements; Manipulation of signalling currents using combinations of direct currents of different amplitudes or polarities over line conductors or combination of line conductors