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公开(公告)号：US06456713B1
公开(公告)日：2002-09-24
申请号：US09109609
申请日：1998-07-02
IPC分类号： H04M100
CPC分类号： H04M11/06 , H04M3/42314
摘要： A circuit for notifying a PBX that a data port in a telephone connected to the PBX is about to be used. The circuit comprises a current sensor for generating a signal that indicates a modem is drawing current through the data port. A large resistor limits the current being drawn through the data port to a level that does not indicate an off-hook condition to either the PBX or the modem. In response to the signal generated by the current sensor, a separate telephone circuit provides an off-hook condition that draws a first dial tone from the PBX. A microprocessor in the circuit generates a signal that causes a dialer in the telephone circuit to dial a number that notifies the PBX that the modem is attempting to access the PBX through the data port. After the PBX is notified of the imminent data port usage, it presents a second dial tone on line two which is the dial tone for an outside line. The microprocessor then activates a thyristor which electrically bypasses the resistor and allows sufficient current to be drawn by the modem to maintain the off-hook condition.
摘要翻译： 用于通知PBX的电路将要使用连接到集团电话的电话中的数据端口。 该电路包括用于产生指示调制解调器正在通过数据端口绘制电流的信号的电流传感器。 一个大电阻将通过数据端口吸取的电流限制在不表示PBX或调制解调器的摘机状态的水平。 响应于由电流传感器产生的信号，单独的电话电路提供从PBX抽取第一拨号音的摘机状态。 电路中的微处理器产生一个信号，使得电话电路中的拨号器拨打一个号码，该号码通知PBX调制解调器试图通过数据端口访问PBX。 在PBX被通知即将来临的数据端口使用之后，它会在第二行显示第二个拨号音，这是外线的拨号音。 然后微处理器激活电路旁路电阻器的晶闸管，并允许调制解调器提供足够的电流以保持摘机状态。
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公开(公告)号：US5768366A
公开(公告)日：1998-06-16
申请号：US832485
申请日：1997-04-02
摘要： A message waiting circuit comprised of a pair of electrical leads which carry a message waiting signal, a capacitor for storing electrical energy extracted from the message waiting signal, a transistor for allowing the capacitor to charge when the message waiting signal is within a predetermined range; a Darlington transistor for causing the capacitor to discharge; and a light emitting diode (LED) which emits light when the capacitor discharges. The flashing LED indicates that a message is waiting for a user of the telephone set associated with the message waiting circuit. Approximately ten to twenty-five message waiting circuits and associated telephone sets can be connected to a single telephone line.
摘要翻译： 一种消息等待电路，包括一对携带消息等待信号的电引线，用于存储从消息等待信号中提取的电能的电容器;当消息等待信号在预定范围内时允许电容器充电的晶体管; 用于使电容器放电的达林顿晶体管; 以及当电容器放电时发光的发光二极管（LED）。 闪烁的LED指示消息正在等待与消息等待电路相关联的电话机的用户。 大约十到二十五个消息等待电路和相关联的电话机可以连接到单个电话线。
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公开(公告)号：US06252957B1
公开(公告)日：2001-06-26
申请号：US09168297
申请日：1998-10-07
IPC分类号： H04M100
CPC分类号： H04M1/72
摘要： A line-powered circuit for connecting a telephone line to a telephone voice circuit comprised of a digital part and an analog part. The digital part is a logic circuit for generating a line connect signal that indicates a telephone line should be connected to the voice circuit. The power for operating the logic circuit is provided by the line voltage associated with the tip and ring leads of the telephone line. The analog part comprises a first switch means for connecting the voice circuit to the tip lead in response to the line connect signal, and a second switch means for connecting the voice circuit to a ring lead in response to the line connect signal.
摘要翻译： 一种用于将电话线连接到由数字部分和模拟部分组成的电话语音电路的线路供电电路。 数字部分是用于产生指示电话线应该连接到语音电路的线路连接信号的逻辑电路。 用于操作逻辑电路的电源由与电话线的尖端和环形引线相关联的线路电压提供。 模拟部分包括用于响应于线路连接信号将语音电路连接到尖端引线的第一开关装置和用于响应于线路连接信号将语音电路连接到环形引线的第二开关装置。
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