Call eavesdropping arrangement

Call processing using previously obtained line characteristics

Canceller trained echo suppressor

Circuit arrangement for generating charge pulses

Circuit arrangement for providing power for an IC chip in a tele

Circuit compensating for the attenuation of a notch filter at fr

Circuit for monitoring battery voltages of telephone terminal fa

Circuit for remote supply of subscriber line terminals in a tele

Circuit for telephone set comprising a light-emitting diode powe

Combination exterior telephone service terminal and splicing...

Communication system with active noise cancellation

Constant current line circuit

Constant power telephone line circuit

Cordless phone with time-out controlled ringer

Cordless telephone outlet device

Cover for a remote terminal

Current limited subscriber interface circuit

Current limiting battery feed arrangement

Current supply circuit