Latching relay drive circuit for use in telephone sets
Limiting maximum gain in duplex communications devices...
Line interface with analog echo cancellation
Line powered universal telephone amplifier
Line use indicator in a telephone set
Long distance bidirectional driver
Loop gain processing system for speakerphone applications
Loudspeaker gain correction for a hands-free telephone terminal
Loudspeaker telephone device comprising a novel noise suppressin
Loudspeaker volume range control
Loudspeaking telephone instrument
Loudspeaking telephone set having an anti-Larsen device for inst
Loudspeaking telephone station including directional microphone
Loudspeaking telephone with a frequency shifting circuit
Low current signal compression circuit
Low power dialer
Low-pass filtering device with integrated insulator and...