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公开(公告)号：US4169248A
公开(公告)日：1979-09-25
申请号：US883786
申请日：1978-03-06
CPC分类号： H03D1/229 , H03B27/00 , H03B5/1215 , H03B5/1231 , H03B2200/0034 , H03B2200/0078 , H03B2200/0098
摘要： An oscillating circuit provides first and second reference signals having a phase difference of 90.degree. with respect to each other. The oscillating circuit includes an oscillator providing the first reference signal at an output thereof, a voltage-to-current converting circuit, which may incorporate a common-base transistor, and a capacitor connected between the output of the oscillator and an input of the converting circuit. The output of the converting circuit then provides the second reference signal which differs in phase by 90.degree. from the first reference signal. The oscillator may include differentially connected transistors and an LC resonant circuit.
摘要翻译： 振荡电路提供相对于彼此具有90°的相位差的第一和第二参考信号。 振荡电路包括在其输出处提供第一参考信号的振荡器，可以结合公共基极晶体管的电压 - 电流转换电路和连接在振荡器的输出端和转换器的输入端之间的电容器 电路。 然后，转换电路的输出提供与第一参考信号相位相差90°的第二参考信号。 振荡器可以包括差分连接的晶体管和LC谐振电路。
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公开(公告)号：US4238771A
公开(公告)日：1980-12-09
申请号：US886427
申请日：1978-03-14
摘要： A muting circuit for a television or AM signal receiver which uses a synchronous detector.The muting circuit includes an input terminal for receiving an amplitude modulated signal, a synchronous detector for detecting such AM signal, a circuit for supplying a reference signal having a predetermined frequency and phase to the synchronous detector, an amplifier, a circuit path for delivering to the amplifier the detected signal produced by the synchronous detector, a level detecting device connected to the output of the synchronous detector for producing an excess signal when the detected signal exceeds a predetermined level, an integrator for producing a muting signal in response to the production over an extended period of time of the excess signal, and a switching device connected to the amplifier for muting the signal produced by the amplifier in response to the production of the muting signal.
摘要翻译： 一种使用同步检波器的电视或AM信号接收机的静音电路。 静音电路包括用于接收幅度调制信号的输入端子，用于检测这种AM信号的同步检波器，用于向同步检测器提供具有预定频率和相位的参考信号的电路，放大器，用于传送到 放大器由同步检测器产生的检测信号，电平检测装置连接到同步检测器的输出端，用于当检测信号超过预定电平时产生过量信号;积分器，用于响应于生产过程产生静噪信号 多余信号的延长的时间段以及连接到放大器的开关装置，用于根据产生的静噪信号使由放大器产生的信号静音。
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3.发明授权
公开(公告)号：US4156255A
公开(公告)日：1979-05-22
申请号：US833710
申请日：1977-09-15
CPC分类号： H03J7/045 , H03D1/2281 , H04B1/26
摘要： A television receiver has an automatic fine tuning circuit with a first phase-locked loop including a first low pass filter and a synchronous video detector with a second phase-locked loop including a second low pass filter. The cut off frequency of the first low pass filter is selected lower than the cut-off frequency of the second low pass filter, thereby enabling a stable operation of two phase-locked loops simultaneously.
摘要翻译： 电视接收机具有自动微调电路，其具有包括第一低通滤波器和同步视频检测器的第一锁相环，其具有包括第二低通滤波器的第二锁相环。 第一低通滤波器的截止频率选择为低于第二低通滤波器的截止频率，从而能够同时稳定地操作两个锁相环。
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公开(公告)号：US4163196A
公开(公告)日：1979-07-31
申请号：US891279
申请日：1978-03-29
摘要： Demodulating apparatus for a modulated signal comprised of a carrier deriving circuit which is supplied with the modulated signal and which derives an unmodulated carrier therefrom, the carrier deriving circuit including a tuned circuit having a center frequency substantially coincident with the carrier frequency of the modulated signal and a limiter circuit in which the limiter circuit imparts a phase shift to the signal supplied thereto in connection with its elimination of the amplitude fluctuations in the signal produced by the tuned circuit. A synchronous detector receives the modulated signal and the derived carrier so as to detect the modulated signal with the derived carrier. A phase shift circuit supplies the synchronous detector with a phase shifted modulated signal, the phase shift substantially compensating for the phase shift imparted by the limited circuit in the carrier deriving circuit, whereby the modulated signal and the carrier which are applied to the synchronous detector are substantially in phase with each other.
摘要翻译： 一种调制信号的解调装置，包括一个载波导出电路，该载波导出电路被提供有调制信号，并从其中导出未调制的载波，该载波导出电路包括调谐电路，该调谐电路的中心频率与调制信号的载波频率基本一致， 限制器电路，其中限制器电路相对于消除由调谐电路产生的信号中的振幅波动而向所提供的信号施加相移。 同步检测器接收调制信号和导出载波，以便用导出的载波检测调制信号。 相移电路为同步检波器提供相移调制信号，相移基本上补偿由载波导出电路中的受限电路产生的相移，由此调制信号和施加到同步检波器的载波是 基本上彼此同相。
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公开(公告)号：US4234963A
公开(公告)日：1980-11-18
申请号：US906406
申请日：1978-05-16
摘要： A synchronous detector adapted to detect a modulated information signal, such as a video IF signal. The modulated information signal is provided in the form of a vestigial sideband signal. A band-pass filter including a tuned circuit tuned to the frequency of the carrier on which the information signal is modulated has a pass band which is less than the frequency spectrum of the vestigial sideband signal so as to limit the frequency spectrum of the signal passed by the filter to a double sideband signal. A limiter is coupled to the band-pass filter to receive the double sideband signal and for deriving a switching carrier therefrom, the frequency of the switching carrier being equal to the frequency of the carrier on which the information signal is modulated. An emitter-follower circuit is connected between the band-pass filter and the limiter so as to couple the double sideband signal from the filter to the limiter. A multiplier circuit has first input terminals coupled to the limiter for receiving the derived switching carrier and second input terminals for receiving the modulated information signal, whereby the modulated information signal is multiplied with the switching carrier to obtain the information signal.
摘要翻译： 一种适用于检测诸如视频IF信号的调制信息信号的同步检测器。 调制信息信号以残留边带信号的形式提供。 包括被调谐到信号信号被调制的载波的频率的调谐电路的带通滤波器具有小于残留边带信号的频谱的通带，以限制通过的信号的频谱 通过滤波器到双边带信号。 限幅器耦合到带通滤波器以接收双边带信号并从其导出交换载波，切换载波的频率等于信息信号被调制的载波的频率。 射频跟随器电路连接在带通滤波器和限幅器之间，以将来自滤波器的双边带信号耦合到限幅器。 乘法器电路具有耦合到限幅器的第一输入端子，用于接收导出的切换载波和用于接收调制信息信号的第二输入端，由此将调制信息信号与切换载波相乘以获得信息信号。
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公开(公告)号：US4110635A
公开(公告)日：1978-08-29
申请号：US715630
申请日：1976-08-18
CPC分类号： H03D1/229 , H03F3/04 , H03F3/42 , H03F3/45089 , H04N5/455
摘要： An amplifier provides a complete video and sound I.F. signal to a synchronous detector switching circuit, and the switching signal to be applied to the switching circuit is obtained from the same amplifier by connecting a grounded base stage, with its emitter impedance, in series with the amplifier load. The grounded base stage has a load tuned to the I.F. carrier frequency, and the filtered signal from the grounded base is the signal applied as the switching signal to the synchronous detector switching circuit.
摘要翻译： 放大器提供完整的视频和声音I.F. 信号发送到同步检测器开关电路，并且通过将接地基站与发射极阻抗串联连接到放大器负载，从同一放大器获得施加到开关电路的开关信号。 接地基座有一个负载调谐到I.F. 载波频率，并且来自接地基极的滤波信号是作为切换信号施加到同步检波器开关电路的信号。
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公开(公告)号：US4115737A
公开(公告)日：1978-09-19
申请号：US851283
申请日：1977-11-14
申请人： Masayuki Hongu , Tsutomu Niimura , Hiromi Kawakami
发明人： Masayuki Hongu , Tsutomu Niimura , Hiromi Kawakami
摘要： A tuner for receiving signals broadcast on two spaced bands, each divided into several channels, has two fixed bandpass filters, one to pass all of the channels in the lower band between the lowest frequency f.sub.P of the lowest channel and the highest frequency f.sub.S of the highest channel of the lower band, and the other to pass all of the channels in the upper frequency band between the lowest frequency f.sub.T of the lowest channel and the highest frequency f.sub.W in the highest channel of the upper band. The bandwidth of each channel is f.sub.B. The tuner includes an amplifier and a third filter to which signals of either band are supplied by selective operation of a switch. The third filter has a cut-off frequency below the second harmonic of the lowest frequency of the upper band to simplify the avoidance of image interference from second harmonic signals of the band. A tunable local oscillator supplies a heterodyning signal to the mixer to convert any selected channel of the received signal to an intermediate frequency (i.f.) band, and image interference is avoided by setting the local oscillator frequency f.sub.n required to convert channel n to the i.f. at a frequency above that channel such that the lowest frequency f.sub.L of the i.f. band satisfies the following conditions: ##EQU1##
摘要翻译： 用于接收在两个间隔的频带上广播的信号的调谐器，每个分成几个信道，具有两个固定带通滤波器，一个通过最低信道的最低频率fP和最低频率的最高频率fS之间的较低频带中的所有信道 较低频带的最高频道，另一方通过最高频带的最低频率fT和上频段最高频道中最高频率fW之间的上频段中的所有频道。 每个通道的带宽为fB。 调谐器包括放大器和第三滤波器，通过开关的选择性操作来提供任一频带的信号。 第三滤波器具有低于上频带最低频率的二次谐波的截止频率，以简化避免来自频带二次谐波信号的图像干扰。 可调本地振荡器向混频器提供外差信号以将接收信号的任何所选信道转换为中频（i.f.）频带，并且通过将通道n转换为i.f来设置所需的本地振荡器频率fn来避免图像干扰。 在该频道之上的频率处，使得i.f.的最低频率fL。 带满足以下条件：
（1） （2）和 或（3） -
公开(公告)号：US4132952A
公开(公告)日：1979-01-02
申请号：US873963
申请日：1978-01-31
申请人： Masayuki Hongu , Tsutomu Niimura , Hiromi Kawakami
发明人： Masayuki Hongu , Tsutomu Niimura , Hiromi Kawakami
摘要： A tuner for receiving signals broadcast on two spaced bands, each divided into several channels, has two fixed bandpass filters, one to pass all of the channels in the lower frequency band and the other to pass all of the channels in the higher frequency band. The tuner includes a mixer to which signals of either band are supplied by selective operation of a double-throw switch. A tunable local oscillator supplies a heterodyning signal to the mixer to convert any selected channel of the received signal to an intermediate frequency (i.f.) band chosen to avoid image interference from undesired channels, whether the local oscillator frequency is above or below the selected channel. To ease the constraints on the choice of the i.f. band, different i.f. filters tuned to first and second i.f. bands may be used for the higher and lower received bands. A second double-throw switch ganged with the first switch can then be used to direct the heterodyned signals to the proper i.f. filter.
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公开(公告)号：US3987317A
公开(公告)日：1976-10-19
申请号：US635365
申请日：1975-11-26
申请人： Masayuki Hongu , Shigeru Ohmuro , Hiromi Kawakami
发明人： Masayuki Hongu , Shigeru Ohmuro , Hiromi Kawakami
CPC分类号： H03F1/302
摘要： A transistor biasing circuit having a single biasing transistor for biasing first and second operational transistors. The biasing transistor has means connecting its base to its collector and means are provided to connect the base of each of the first and second operational transistors to the collector circuit of the biasing transistor. Each of the three transistors are arranged in a circuit between a pair of voltage terminals which are connected to a power supply. The arrangement of the resistors in the circuit paths of the biasing transistor and the operational transistors are in such a way as to provide circuit means for stabilizing the collector currents of the first and second transistors regardless of variations in the factor of h.sub.FE. This circuit arrangement provides an improved stabilization of the collector currents over prior art devices.
摘要翻译： 一种晶体管偏置电路，具有用于偏置第一和第二操作晶体管的单个偏置晶体管。 偏压晶体管具有将其基极连接到其集电极的装置，并且提供装置以将第一和第二操作晶体管中的每一个的基极连接到偏置晶体管的集电极电路。 三个晶体管中的每一个被布置在连接到电源的一对电压端子之间的电路中。 偏置晶体管和操作晶体管的电路中的电阻器的排列方式是提供用于稳定第一和第二晶体管的集电极电流的电路装置，而与hFE因子的变化无关。 该电路布置提供了集电极电流相对于现有技术装置的改进的稳定性。
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公开(公告)号：US4419695A
公开(公告)日：1983-12-06
申请号：US341465
申请日：1982-01-21
IPC分类号： H04N5/60
CPC分类号： H04N5/607
摘要： A television sound receiver having an input terminal for receiving a television sound signal, a tuner including a local oscillator connected to the input terminal, an intercarrier sound demodulating circuit connected to the tuner, a split-carrier sound demodulating circuit, including a limiter amplifier connected to the tuner, a sound signal output terminal, and a switching device for selectively and operatively connecting either the intercarrier or split-carrier sound demodulating circuits between the tuner and the sound signal output terminal. Additionally, the receiver includes an error detecting device connected to the split-carrier sound demodulating circuit for detecting the frequency error of the local oscillator and a first operational device which is responsive to an output signal from the error detecting device and which produces a first operational device output signal which activates the switching device such that the split-carrier sound demodulating circuit is operatively connected between the tuner and the sound output terminal when the output signal from the error detecting device is less than a predetermined level. Level detectors are connected to the limiter amplifier and detect a level of the split-carrier sound signal. A second operational device, which is responsive to the output signal from the level detectors, produces an output signal which activates the switching device such that the intercarrier sound demodulating circuit is operatively connected between the tuner and the sound output terminal when the output signals from the level detectors are less than a predetermined value.
摘要翻译： 一种具有用于接收电视声音信号的输入端子的电视声音接收器，包括连接到输入端子的本地振荡器的调谐器，连接到调谐器的载波间声音解调电路，分离载波声音解调电路，包括限幅放大器 调谐器，声音信号输出端子和用于选择性地和可操作地连接调谐器和声音信号输出端子之间的载波间或分离载波声音解调电路的开关装置。 此外，接收机包括连接到分离载波声音解调电路以检测本地振荡器的频率误差的误差检测装置和响应于来自错误检测装置的输出信号并且产生第一操作的第一操作装置 装置输出信号，其激活开关装置，使得当来自误差检测装置的输出信号小于预定电平时，分离载波声音解调电路可操作地连接在调谐器和声音输出端子之间。 电平检测器连接到限幅放大器并检测分离载波声音信号的电平。 响应于来自电平检测器的输出信号的第二操作装置产生激活开关装置的输出信号，使得当来自所述开关装置的输出信号时，载波间声音解调电路可操作地连接在调谐器和声音输出端子之间 电平检测器小于预定值。
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