| 摘要 |
An alarm system for indicating unauthorized movement of an article includes a pendulum type motion responsive switch having a conically shaped suspended contact disposed within an annular contact. Adjustment of the height of the two contacts relative to each other provides for a variation in the sensitivity of the switch. A plurality of single-pole, double-throw switches connected in parallel with each other and having one output terminal cut or disabled to provide an open circuit condition provides for the selective disabling of the alarm system only by setting each of the switches in accordance with a predetermined key combination. All of the components of the system are self-contained on a cover that is secured to a casing which encloses the components and is attached to the article being protected. The cover is secured to the casing by bolts which form an operative component of tamper detection switches for actuating the alarm when an unauthorized attempt is made to remove the cover from the casing.
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