| 摘要 |
<p>The anti-theft device has a battery powered siren fitted inside the vehicle, and uses a telescopic rod fitted to the floor of the vehicle and projecting downwards. The device is armed by moving the rod downwards till it is in contact with the ground. The rod is then locked in place. If the vehicle is disturbed a magnetic ball moves to a position where it closes the contacts to the siren. The enclosure of the siren has contacts fitted to it so that, when opened, the siren is activated.</p> |
