3621112 - Telephone switching, switchboard and line equipment
All examples - 3621112 - Telephone switching, switchboard and line equipment
- digital line systems apparatus
- electronic switching apparatus for telephone central office
- modulators for carrier-current line systems
- multiplex equipment for carrier-current line systems
- private branch exchange (PBX)
- telegraphic switching apparatus
- telephone carrier-current line systems
- telephone switching, switchboard and line equipment
- telephonic switching apparatus for customer
- telephonic switching apparatus, electronic key telephone system
