CPC Main Group
H04M 7/00 Arrangements for interconnection between switching centres
12 direct subcodes
Child Classifications
Navigate with arrow keys, Enter to open
- H04M 7/06 using auxiliary connections for control or supervision
- H04M 7/08 for phantom working
- H04M 7/12 for working between exchanges having different types of switching equipment, e.g. power-driven and step by step or decimal and non-decimal
- H04M 7/14 in systems involving main and subordinate switching centres
- H04M 7/16 in systems employing carrier frequencies