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    Supervisory circuit for electronically monitoring a telegraphy line
    21.
    发明授权
    Supervisory circuit for electronically monitoring a telegraphy line 失效
    用于电子监控电视线的监视电路

    公开(公告)号：US3668314A

    公开(公告)日：1972-06-06

    申请号：US3668314D

    申请日：1969-12-31

    Applicant: CIT ALCATEL

    Inventor： ROUSSEAU CLAUDE

    IPC: H04L25/38 ,  H04L12/26 ,  H04L25/40 ,  H04L29/08 ,  H04L25/02

    CPC classification number: H04L43/00

    Abstract: An electronic supervisory circuit indicates the condition of a telegraphy line being supervised without interfering with the transmission of the telegraphy signals. The supervisory circuit employs a holding circuit responsive to the detection of modulated line signals which maintains the output of the supervisory circuit during the periods when the modulated signals are transmitted over the telegraphy line. An auxiliary output is also employed to indicate the instantaneous condition of the line.

    Abstract translation: 电子监控电路指示监视电报线路的状况，而不干扰电报信号的传输。 监控电路采用保持电路，该保持电路响应于调制线路信号的检测，该调制线路信号在调制信号通过电报线路传输的时段期间保持监控电路的输出。 辅助输出也用于指示线路的瞬时状态。

    Single sideband system with means for compensating for doppler shift
    22.
    发明授权
    Single sideband system with means for compensating for doppler shift 失效
    单边系统，用于补偿多普勒移位

    公开(公告)号：US3634766A

    公开(公告)日：1972-01-11

    申请号：US3634766D

    申请日：1969-03-19

    Applicant: CIT ALCATEL

    Inventor： BOYER MARCEL LOUIS

    IPC: H03J7/06 ,  H03L7/14 ,  H04B1/30 ,  H04B1/68 ,  H04B1/10

    CPC classification number: H03J7/06 ,  H03L7/14 ,  H04B1/302 ,  H04B1/68

    Abstract: A single or independent sideband radio transmitter having a high-frequency section for transmitting a high-frequency signal modulated by a low-frequency bandwidth and which is connected to receive the lower bandwidth section from a speech circuit and the upper bandwidth section from circuitry providing two lateral bands of equal width and equispaced from a reference frequency provided by an oscillator, the generation of the lateral bands being controlled by the speech level, and a radio receiver having separator filters connected to isolate respective subbands of equal width from an upper section of a received frequency spectrum containing speech modulation components, modulating and filtering circuitry provided with a fixed-frequency local oscillator and deriving from the subbands and the oscillator output a signal having a frequency which is significant of the carrier frequency as modified by an uncontrollable frequency deviation. a demodulator fed by a variable-frequency oscillator and by the lower section of the signal frequency spectrum, and a system controlling the operating frequency of the variable oscillator in accordance with the output of a discriminator which compares the variable oscillator output frequency with said signal from said modulating and filtering circuitry.

    System for remote supervision of repeaters
    23.
    发明授权
    System for remote supervision of repeaters 失效
    远程监控系统

    公开(公告)号：US3557323A

    公开(公告)日：1971-01-19

    申请号：US3557323D

    申请日：1968-03-26

    Applicant: CIT ALCATEL

    Inventor： CHALHOUB CHRISTIAN

    IPC: H04B17/40 ,  H04B3/46

    CPC classification number: H04B17/403

    Abstract: A system for remote supervision of repeaters in a telecommunication line wherein each repeater includes a frequency generator supplying a frequency characteristic of the repeater, a control arrangement for passing the output of the frequency generator for all but one given level of an applied control signal and a rectifier device for producing the control signal proportional to the output of the primary amplifier in the repeater, the telecommunication line having an additional generator of a frequency of variable level connected to the input of the line and an indicator for detecting the level of the signal generated by the frequency generator of a particular repeater.

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