| 摘要 |
<p>A telephone adaptor unit (6) for a telephone set connectible, with other like telephone adaptor units for other telephone sets, between the respective telephone set and a common telephone line (2), includes a first switching device (14) effective, when an off-hook condition is detected, to connect the respective telephone set to the telephone line and to disconnect the other telephone sets from the line, an audio circuit including a speaker (18), a second switching device (22) for enabling the audio circuit to receive audio signals from the line and to reproduce such signal via its speaker, and a control system effective to actuate the first switching device of the other units to connect their respective telephone sets to the line, and to actuate the second switching device of the other units to enable the audio circuit of the other units to receive audio signals from the line and to reproduce such signals via their speakers.</p> |
