| 摘要 |
<p>The roof mounted emergency signal has two sets of exponential, acoustic horns directed fore and aft. The forward facing horn provides a louder tone than the rearwards facing one, both for siren and loudspeaker. The top of the signal carries the flasher light. The rear of the signal has an illuminated sign which also serves as a rectangular cover for the loudspeaker. The system can be selected in its mode of operation by dashboard switches. It provides the loudest intensity where it is most required, without undue disturbance elsewhere.</p> |
