Circuit arrangement for suppressing interference signals on the
Circuit arrangement for telecommunications exchange systems, par
Circuit arrangement for telecommunications switching systems, pa
Circuit arrangement for telecommunications switching systems, pa
Circuit arrangement for telecommunications switching systems, pa
Circuit for generating metering pulses intended for presentation
City, time and toll-charge display when calling telephone number
Coil operated telephone
Coin operated telephone
Collaborative conference bridges
Collect callback
Collect credit card service
Communication assistance system and method
Communication charge calculating apparatus, control method...
Communication charge management system
Communication control system and communication control method
Communication control system and communication control method
Communication gateway system
Communication line monitoring system
Communication line monitoring system