Auxiliary attenuator arrangement for use in voice-switched speak
Bell sound synthesizer
Bookmarking method and apparatus for an electronic phone book
Busy/no-answer call completion equipment
Call management system
Call notification system, method, computer program and...
Call progress decoder for multiple cadenced tones on telephone l
Call progress monitor circuitry and method for a...
Call signal detecting device
Call transmitter for the input of control commands,...
Call-routing device
Called party response detecting apparatus
Caller controlled network-based timed ring suppression
Caller identification interface using line reversal detection
Caller-identification receiving apparatus
Canonical telephone numbers
Capacitively coupled ring detector with power provided...
Card system
Card-like device having a microprocessor and speaker for communi
CAS tone disguising method and apparatus