IPC Subgroup
H04M 1/57 Arrangements for indicating or recording the number of the calling subscriber at the called subscriber's set
Introduced: July 1974
Last revised: January 2006
Full Title
Substation equipment, e.g. for use by subscribers > Arrangements for indicating or recording the number of the calling subscriber at the called subscriber's set
Classification Context
- Section:
- ELECTRICITY
- Class:
- ELECTRIC COMMUNICATION TECHNIQUE
- Subclass:
- TELEPHONIC COMMUNICATION