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    Repeater for transmission lines of differing lengths
    3.
    发明授权
    Repeater for transmission lines of differing lengths 失效
    不同长度传输线的重复

    公开(公告)号：US4032726A

    公开(公告)日：1977-06-28

    申请号：US703556

    申请日：1976-07-08

    申请人： Charles W. Chambers, Jr.

    发明人： Charles W. Chambers, Jr.

    IPC分类号： H04B3/16 ,  H04B3/36

    CPC分类号： H04B3/16 ,  H04B3/36

    摘要： A circuit for varying the amplification afforded to a-c signals transmitted through a transmission line in accordance with the a-c losses of that transmission line. Gain control circuitry is provided which varies the magnitude of amplifying voltages and currents inserted into the transmission line in accordance with the a-c losses of that transmission line. The gain control circuitry is comprised of a line resistance sensor which establishes a contol signal which is a function of the a-c losses of the transmission line. This control signal is applied to the remainder of the gain control circuitry to vary the magnitude of voltages and currents inserted into the transmission line in accordance with that control signal. As a result, the gain control circuitry automatically adjusts the gain of a repeater in accordance with each transmission line connected thereto.

    Negative impedance repeater for telephone lines
    4.
    发明授权
    Negative impedance repeater for telephone lines 失效
    用于电话线路的负阻抗中继器

    公开(公告)号：US4028505A

    公开(公告)日：1977-06-07

    申请号：US619905

    申请日：1975-10-06

    申请人： Lorenzo Fassino

    发明人： Lorenzo Fassino

    IPC分类号： H03H11/44 ,  H04B3/16 ,  H04B3/36

    CPC分类号： H03H11/44 ,  H04B3/16

    摘要： A negative impedance repeater for amplification in telephone lines operating at voice frequency comprises two converters, one of them stable with open terminals and the other stable with short-circuited terminals; each converter is loaded by a fixed network of passive impedances chosen according to the characteristic impedance of the line to be amplified, and provided with means, external to the network of passive impedances, for adjusting the feedback, and consequently the conversion ratio. The conversion ratios of the two converters may be varied independently from each other so that in the case of loaded lines their product may be kept always constant and this allows to adjust the repeater gain without modifying its impedance, while for unloaded lines it is possible to obtain that such product increases with a certain law by increasing gain, and this fact causes an equalization at the highest frequencies of the band, which is necessary for this type of lines.

    摘要翻译： 用于在语音频率下工作的电话线路中用于放大的负阻抗中继器包括两个转换器，其中一个稳定，具有开路端子，另一个稳定的具有短路端子; 每个转换器由根据要放大的线路的特性阻抗选择的无源阻抗的固定网络加载，并且在被动阻抗网络外部提供用于调整反馈的装置，从而提供转换比。 两个转换器的转换比可以彼此独立地变化，使得在负载线路的情况下，它们的乘积可以保持总是恒定的，并且这允许调整中继器增益而不修改其阻抗，而对于无负载线路，可以 通过增加增益获得这种产品通过某种规律增加，并且这个事实导致频带的最高频率的均衡，这对于这种类型的线路是必需的。

    Negative impedance repeater
    5.
    发明授权
    Negative impedance repeater 失效
    负阻抗中继器

    公开(公告)号：US3927280A

    公开(公告)日：1975-12-16

    申请号：US46964374

    申请日：1974-05-13

    申请人： WESCOM

    发明人： GUPTA SHANTI S ,  PERSHING ROBERT G

    IPC分类号： H04B3/16 ,  H04B3/18 ,  H04B3/36

    CPC分类号： H04B3/16

    摘要： A negative impedance repeater, particularly suited for use with non-loaded metallic transmission facilities, including a bridgedT series-shunt negative impedance gain unit, and an active impedance correcting unit for matching the impedance of the facility to the fixed image impedance of the gain unit. The impedance corrector, which may be modeled as a variable resistor (positive or negative) in series with a variable negative capacitor, is adapted to decrease the impedance of the facility below a predetermined crossover frequency, and increase its impedance above that frequency. The gain unit is arranged to provide a gain vs. frequency characteristic which is sloped to complement the attenuation vs. frequency slope of corrected transmission facilities.

    摘要翻译： 一种负阻抗中继器，特别适用于非负载金属传输设施，包括桥接T串并联负阻抗增益单元，以及有源阻抗校正单元，用于将设备的阻抗与固定图像阻抗匹配 增益单位。 阻抗校正器可以被建模为与可变负电容器串联的可变电阻器（正或负）），适于将设备的阻抗降低到预定的交越频率以下，并将其阻抗增加到高于该频率。 增益单元被布置成提供增益对频率特性，其被倾斜以补偿校正的传输设施的衰减对频率斜率。