IPC Subgroup
H04M 3/428 Arrangements for placing incoming calls on hold
Introduced: January 2000
Last revised: January 2006
Full Title
Automatic or semi-automatic exchanges > Systems providing special services or facilities to subscribers > Arrangements for placing incoming calls on hold
Classification Context
- Section:
- ELECTRICITY
- Class:
- ELECTRIC COMMUNICATION TECHNIQUE
- Subclass:
- TELEPHONIC COMMUNICATION