| 摘要 |
<p>In the device for protection against burglaries, a fine conducting wire (7) is buried in a wall covering (6) covering the wall to be protected; the wire is linked to a measuring bridge (10, 11, 12), one diagonal of which is supplied by a source (14), the other diagonal connected to an amplifier (18). The latter drives a comparator circuit (25, 26) whose reference inputs are linked to a divider bridge (28, 29, 30) and to an astable generator (33). The alarm circuits include the logic operators (36, 37, 38) and alarm devices (39 and 40). The device can be used for protection of strongrooms and safes. <IMAGE></p> |
