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PCE
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DIFF Subgroup
H04Q 1/38

using combinations of direct currents of different amplitudes or polarities over line conductors or combination of line conductors

Introduced: September 1968

Full Title

Full titles differ between systems:

IPC:

Details of selecting apparatus or arrangements > Electrical details > Signalling arrangements; Manipulation of signalling currents > using combinations of direct currents of different amplitudes or polarities over line conductors or combination of line conductors

CPC:

Details of selecting apparatus or arrangements > Electrical details > Signalling arrangements; Manipulation of signalling currents (multiplex systems providing for calling or supervisory signals H04J1/14, H04J3/12) > using combinations of direct currents of different amplitudes or polarities over line conductors or combination of line conductors

No child classifications to compare. This is a leaf node in both IPC and CPC.