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公开(公告)号：US06690279B1
公开(公告)日：2004-02-10
申请号：US09493932
申请日：2000-01-28
IPC分类号： G08B1314
CPC分类号： G08B13/2408 , G08B13/2448
摘要： The invention is directed to a security element for the electronic surveillance of articles. This security element is detected by surveillance systems operating in different frequency ranges and it includes at least two materials of high permeability which, when excited by an external alternating magnetic field emit each a characteristic signal. The maximum signal components of the two materials lie in different frequency ranges and the signal components of the one material are negligibly ow in that particular frequency range in which the signal component of the other material is at a maximum level. The invention also relates to surveillance systems that incorporate these security elements.
摘要翻译： 本发明涉及用于物品的电子监视的安全元件。 该安全元件由在不同频率范围内工作的监控系统检测到，并且包括至少两种高磁导率材料，当外部交变磁场激发时，它们发出特征信号。 两种材料的最大信号分量位于不同的频率范围内，并且一种材料的信号分量在其他材料的信号分量处于最大水平的特定频率范围内可忽略不计。 本发明还涉及包含这些安全元件的监视系统。
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公开(公告)号：US4363004A
公开(公告)日：1982-12-07
申请号：US198831
申请日：1980-10-20
摘要： A combining and filter circuit is provided to connect the acquisition circuit and phase detector circuit to the voltage controlled oscillator in a phase locked loop. The combining and filter circuit includes twin-T filters for removing reference frequency signals. An output circuit includes series resistors and capacitors, and reverse poled Schottky diodes which provide rapidly changing acquisition signals that are relatively noise free.
摘要翻译： 提供组合和滤波电路，用于将采集电路和相位检测器电路连接到锁相环中的压控振荡器。 组合和滤波电路包括用于去除参考频率信号的双T滤波器。 输出电路包括串联电阻器和电容器，反向极化肖特基二极管提供相对无噪声的快速变化的采集信号。
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公开(公告)号：US4450416A
公开(公告)日：1984-05-22
申请号：US293395
申请日：1981-08-17
申请人： Gregory N. Mears
发明人： Gregory N. Mears
CPC分类号： H03B5/1228 , H03B5/1203 , H03B5/1243 , H03B2200/0008 , H03B2200/004 , H03B2200/0092 , H03B2201/0208
摘要： A voltage controlled oscillator is provided with one or more varactors connected in series with the frequency determining capacitors of the oscillator. These varactors are in addition to prior art varactors, and increase the tunable range of the oscillator, and improve the frequency variation with control voltage characteristic of the oscillator.
摘要翻译： 压控振荡器设置有与振荡器的频率确定电容器串联连接的一个或多个变容二极管。 这些变容二极管是现有技术的变容二极管，并且增加了振荡器的可调谐范围，并且通过振荡器的控制电压特性来改善频率变化。
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公开(公告)号：US4430756A
公开(公告)日：1984-02-07
申请号：US350981
申请日：1982-02-22
申请人： Rodney A. Dolman , Gregory N. Mears
发明人： Rodney A. Dolman , Gregory N. Mears
摘要： An oscillator is controlled so that it produces the correct frequency in the transmitting condition, and so that it produces a slightly different frequency in the receiving condition. This is achieved by a circuit which supplies a first control voltage to the oscillator for transmitting and which supplies a second and different control voltage to the oscillator for receiving. This second and different control voltage causes the oscillator frequency in the receiving condition to be different so that there is no interference to or improper operation of a repeater system. The circuit also prevents any modulation signals from reaching the oscillator in the receiving condition, thus preventing false signals or other problems.
摘要翻译： 控制振荡器使得其在发送状态下产生正确的频率，并且使得其在接收状态下产生稍微不同的频率。 这是通过向振荡器提供第一控制电压以传输并向振荡器提供第二和不同的控制电压以供接收的电路来实现的。 该第二和不同的控制电压导致接收状态下的振荡器频率不同，使得不对中继器系统产生干扰或不正确的操作。 该电路还防止任何调制信号在接收状态下到达振荡器，从而防止假信号或其他问题。
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