Integrated ringer relay circuit and method
Method and an arrangement for generating a ringing signal
Method and apparatus for operating a telephone exchange having s
Method and apparatus for selectively generating control signals
Method and apparatus for sending alerts to internet protocol...
Method for realizing ring back tone in communication system
Method of automatic equalized distribution of ring loads for tel
Method to reduce distortion of a digital data signal by a...
Monolithically integratable telephone circuit for supplying ring
Monolithically integratable telephone circuit for supplying ring
Personal branch exchange system
Power amplifier
Programmable call progress tones for a switching system
Programmable ring signal generator
Ringback tone service opt-in and opt-out requests for use by...
Ringing signal control circuit capable of suppressing surge volt
Ringing signal sending-out circuit
Solid state ringing switch
Splitter for analog telephone signal and digital data
Subscriber apparatus with ringer generator for sending ringer si