Logic control for electronic key telephone line circuit
Long distance call interceptor
Long distance service bureau
Long distance telephone call limiting device
Long distance telephone switching system with enhanced...
Long distance telephone switching system with enhanced...
Long-line telephone circuit
Loop and rate-dependent ds power cutback for power savings...
Loop arrangement to test a remote subscriber's drop from a...
Loop current detector
Loop detecting circuit
Loop driver for pots, xdsl, or integrated pots/xdsl interface
Loop driver for pots, xdsl, or integrated pots/xdsl interface
Loop extender
Loop fault locator
Loop sensing circuit for use with a subscriber loop...
Loop test circuit
Loop to ground start circuit
Loop, dial pulse and ring trip detection circuit
Loop-back test system using a suppressed ringing connection