IPC Subgroup
H04M 3/06 the calling signal being supplied from the subscriber's line circuit
Introduced: September 1968
Last revised: January 2006
Full Title
Automatic or semi-automatic exchanges > Calling substations, e.g. by ringing > the calling signal being supplied from the subscriber's line circuit
Classification Context
- Section:
- ELECTRICITY
- Class:
- ELECTRIC COMMUNICATION TECHNIQUE
- Subclass:
- TELEPHONIC COMMUNICATION