| 摘要 |
<p>A signal distribution and communication arrangement includes a main control unit (10) remotely located and electrically coupled to a volume control panel (48). The volume control panel (48) is located near a speaker (14), and the main control unit (10) sends substantially continuous audio signals (20) or an interrupting audio signal (22) to the volume control panel for playing via the speaker. These signals can be sent on the same conductor (32) or separate conductors. When the interrupting audio signal (22) is present, a voltage or current source (40) provides a level from the main control unit (10) to the volume control panel (48) to indicate that a volume override circuit (50) should be engaged. Upon engagement of the volume override circuit (50), the interrupting audio signal is passed through to the speaker at a prescribed signal level, regardless of the volume control setting (54) on the volume control panel.</p> |
