Telephone privacy and alerting device

Telephone privacy circuit

Telephone programming system for automated calling

Telephone ringback test device and method

Telephone security violation detection device

Telephone software testing system and method

Telephone subscriber line diagnostics system and method

Telephone subscriber line fault detector

Telephone subscriber loop test system

Telephone switch dual monitors

Telephone system communication mechanism employing central offic

Telephone system diagnostic measurement system including a dista

Telephone system loop current detector

Telephone technician's remote assist apparatus and method

Telephone technician's terminals with auto-selection of dial pul

Telephone test device

Telephone test device and method of the same for optical cable t

Telephone test instrument

Telephone test set

Telephone test set having an auxiliary amplifier and speaker for