公开(公告)号：US3824474A

公开(公告)日：1974-07-16

申请号：US29084172

申请日：1972-09-21

申请人： MATSUSHITA ELECTRIC IND CO LTD

发明人： SAKAMOTO Y

IPC分类号： H03J7/10 ,  H04B1/16

CPC分类号： H03J7/10

摘要： An automatic frequency control device for a television receiver is provided in which a DC tuning voltage superposed upon AFC voltage is applied to one end of a varactor in an UHF tuner whereas said DC tuning voltage is applied to one end of a varactor in a VHF tuner and AFC voltage with a polarity opposite to that of the first mentioned AFC voltage is applied to the other end of the varactor.

摘要翻译： 提供了一种用于电视接收机的自动频率控制装置，其中叠加在AFC电压上的DC调谐电压被施加到UHF调谐器中的变容二极管的一端，而所述DC调谐电压被施加到VHF调谐器中的变容二极管的一端 并且将具有与先前提到的AFC电压相反的极性的AFC电压施加到变容二极管的另一端。

公开(公告)号：US3796824A

公开(公告)日：1974-03-12

申请号：US3796824D

申请日：1972-01-26

申请人： ZENITH RADIO CORP

发明人： BAKER R

IPC分类号： H03J7/10 ,  H04N5/50 ,  H04N5/44 ,  H04B1/16

CPC分类号： H04N5/50 ,  H03J7/10

摘要： The automatic frequency control (AFC) system of a television receiver includes a discriminator network and a pair of nonbiased rectifier arrangements with load circuits, operating over a small range of frequency deviations centered about the desired mean frequency. The rectifier arrangements are non-biased for compatibility with varactor tuning systems and include three serially connected diodes in one of the rectifier arrangements and a single diode in the other to achieve extended pull-in. The three serially connected diodes vary the conduction threshold of the positive portion of the discriminator network to assure proper shaping of the frequency response characteristic of the FM detector. Accordingly, for conditions of gross mistuning, control voltages are obtained from the two rectifier arrangements that are of the same polarity and aid one another in obtaining an augmented frequency correcting effect.

摘要翻译： 电视接收机的自动频率控制（AFC）系统包括鉴别器网络和一对具有负载电路的非偏置整流器装置，其以围绕期望的平均频率为中心的小范围的频率偏差运行。 整流器装置没有偏置以与变容二极管调谐系统兼容，并且在整流器装置之一中包括三个串联的二极管，而在另一个整流器装置中包括一个二极管，以实现扩展的拉入。 三个串联连接的二极管改变鉴别器网络的正部分的导通阈值，以确保FM检测器的频率响应特性的适当整形。 因此，对于严重失谐的情况，从具有相同极性的两个整流器装置获得控制电压，并且在获得增强的频率校正效果时彼此相辅相成。

公开(公告)号：US3679990A

公开(公告)日：1972-07-25

申请号：US3679990D

申请日：1971-01-27

申请人： GEN INSTRUMENT CORP

发明人： HIDAY DAVID R ,  MULL RALPH L JR

IPC分类号： H03J7/10 ,  H03B3/04 ,  H03B5/12

CPC分类号： H03J7/10

摘要： A tuned transistor oscillator for use with an RF receiver includes a transistor amplifier having a tuned network coupled between the collector and base of the transistor. Feedback is provided by a capacitor coupled between the tuned network and the emitter of the transistor. The tuned network includes a transmission line, a variable capacitive reactance means in parallel therewith, a first variable capacitance diode in series with said reactance means, and a second variable capacitance diode serially connected to said line. The capacitance of said reactance means is varied to allow the oscillator to sweep the desired frequency range, and the first and second capacitance diodes are varied by a DC AFC (automatic frequency control) voltage provided by the discriminator of the RF receiver to prevent oscillator drift. Said first and second diode capacitances are arranged so that the first capacitance has its greatest effect at the lower end of the oscillator frequency range while the second capacitor has its greatest effect at the upper end of said range, thereby providing an AFC signal which varies the oscillator frequency by a substantially constant amount independently of the oscillator frequency.

摘要翻译： 用于RF接收机的调谐晶体管振荡器包括晶体管放大器，其具有耦合在晶体管的集电极和基极之间的调谐网络。 反馈由耦合在调谐网络和晶体管的发射极之间的电容器提供。 调谐网络包括传输线，与其并联的可变容性电抗装置，与所述电抗装置串联的第一可变电容二极管和串联连接到所述线路的第二可变电容二极管。 所述电抗装置的电容被改变以允许振荡器扫过期望的频率范围，并且第一和第二电容二极管由RF接收器的鉴频器提供的DC AFC（自动频率控制）电压改变，以防止振荡器漂移 。 所述第一和第二二极管电容被布置成使得第一电容在振荡器频率范围的较低端具有最大的影响，而第二电容器在所述范围的上端具有最大的影响，从而提供AFC信号， 振荡器频率与振荡器频率无关，基本恒定。

公开(公告)号：US3609554A

公开(公告)日：1971-09-28

申请号：US3609554D

申请日：1968-10-16

申请人： PHILIPS CORP

发明人： STOKER ALBERT

IPC分类号： H03J7/02 ,  H03J7/10 ,  H03D3/00 ,  H03K7/00

CPC分类号： H03J7/10 ,  H03J7/023

摘要： A circuit for switching a connection point from variable signal to a reference potential, employing a transistor having its control electrode connected to a variable DC voltage, and its emitter-collector path connected by resistors between a potential divider and a reference point. A pair of similarly poled diodes are connected across the emitter-collector path, the junction of said diodes connected to said connection point.

公开(公告)号：US3251008A

公开(公告)日：1966-05-10

申请号：US35033464

申请日：1964-03-09

申请人： KOEHLER REGINA

发明人： GERHARD SCHWEITZER

IPC分类号： H03B1/00 ,  H03B5/12 ,  H03J7/10

CPC分类号： H03J7/10 ,  H03B5/1203 ,  H03B5/1231 ,  H03B5/1243 ,  H03B5/1256 ,  H03B2200/004 ,  H03B2201/0208

公开(公告)号：US09876480B2

公开(公告)日：2018-01-23

申请号：US14060341

申请日：2013-10-22

申请人： Infineon Technologies AG

发明人： Winfried Bakalski

IPC分类号： H03H7/01 ,  H03H11/04 ,  H03J7/10 ,  H03J3/20 ,  H03H1/00

CPC分类号： H03H7/0153 ,  H03H11/04 ,  H03H2001/0014 ,  H03J3/20 ,  H03J7/10 ,  H03J2200/10

摘要： A tunable capacitance circuit comprises a plurality of varactor transistors which are coupled in series. An antenna tuner comprises such a tunable capacitance circuit.

公开(公告)号：US5487186A

公开(公告)日：1996-01-23

申请号：US368747

申请日：1995-01-04

申请人： Carl G. Scarpa

发明人： Carl G. Scarpa

IPC分类号： H04N5/12 ,  H03J7/02 ,  H03J7/10 ,  H03L7/06 ,  H04B1/16

CPC分类号： H03J7/10

摘要： A technique for maintaining a center frequency of an input signal at a nominal center frequency. Apparatus which implements this technique divides, using a pair of bandpass filters (122, 124), the modulation bandwidth of the input signal into two halves (half-bands) and measures the signal strength of the input signal in each half-band. Then, circuitry (126, 128, 130), connected to each filter, compares the signal strengths of the signals passing through each filter. The circuitry produces a difference signal representing a difference between the strength of each signal passing through each respective filter. The difference signal is used to adjust a frequency of a local oscillator signal produced by a local oscillator (112) within a tuner (104) such that the center frequency of the input signal is maintained by the tuner at the nominal center frequency.

摘要翻译： 用于将输入信号的中心频率保持在标称中心频率的技术。 实现该技术的装置使用一对带通滤波器（122,124）将输入信号的调制带宽分成两半（半波段），并测量每个半波段中输入信号的信号强度。 然后，连接到每个滤波器的电路（126,128,130）比较通过每个滤波器的信号的信号强度。 电路产生一个差分信号，表示通过每个滤波器的每个信号的强度之差。 差分信号用于调节由调谐器（104）内的本地振荡器（112）产生的本地振荡器信号的频率，使得输入信号的中心频率由标称中心频率的调谐器维持。

公开(公告)号：US4782532A

公开(公告)日：1988-11-01

申请号：US38563

申请日：1987-04-15

申请人： Lawrence M. Ecklund

发明人： Lawrence M. Ecklund

IPC分类号： H03J7/18 ,  H03D1/22 ,  H03J7/02 ,  H03J7/10 ,  H04B1/26 ,  H04H5/00

CPC分类号： H03J7/10 ,  H03D1/2236

摘要： An improved radio receiver that maintains a stable predetermined IF frequency upon receipt of input carrier signals of differing frequencies. The IF signal (14) is processed through a signal demodulation unit (16) that includes a tangent processing unit (22) to yield a control signal that varies as a tangent function of both the demodulated IF signal and a reference signal from a reference oscillator (17). This control signal is used to control the frequency and phase of a reference signal (26) used by the IF stage (12) to center the IF signal with respect to the IF stage characteristics.

摘要翻译： 一种改进的无线电接收机，其在接收到不同频率的输入载波信号时保持稳定的预定IF频率。 IF信号（14）通过包括切线处理单元（22）的信号解调单元（16）进行处理，以产生作为解调的IF信号和来自基准振荡器的参考信号的切线函数而变化的控制信号 （17）。 该控制信号用于控制由IF级（12）使用的参考信号（26）的频率和相位，以使IF信号相对于IF级特性居中。

公开(公告)号：US4736458A

公开(公告)日：1988-04-05

申请号：US926477

申请日：1986-11-03

申请人： Anthonius J. J. C. Lommers

发明人： Anthonius J. J. C. Lommers

IPC分类号： H03J7/02 ,  H03J7/10 ,  H03J1/16 ,  H03L7/00

CPC分类号： H03J7/10

摘要： Receiver (1-9) provided with a frequency control loop (2-6) for automatic fine tuning, consecutively incorporating a controllable oscillator (6) which is tunable in frequency by means of a variable capacitance diode (D), a mixer stage (2) to which the signal from the controllable oscillator (6) is applied for converting an RF receiver signal into an intermediate frequency signal, a frequency voltage converter (4) tuned to a fixed intermediate frequency for converting frequency deviations of the intermediate frequency signal relative to the fixed intermediate frequency into amplitude variations of the frequency voltage converter (4) output signal relative to a refrence value, a control signal generating circuit (5) for deriving a control signal for the variable capacitance diode (D) of the controllable oscillator (6) from the output signal of the frequency voltage converter (4), which at least partly compensates the asymmetrical diode capacitance-voltage characteristic. In order to prevent unwanted side-tuning effects from occuring during this compensation, the frequency-dependent variation of the control signal for the variable capacitance diode (D) is to assume an asymmetrical S curve which is curved around the maximum values therein and which compensates the asymmetry in the diode capacitance variation.

摘要翻译： 接收器（1-9）具有用于自动微调的频率控制回路（2-6），连续地结合了可调谐振荡器（6），该可控振荡器通过可变电容二极管（D），混频器级（D） 2）来自可控振荡器（6）的信号被施加到其中以将RF接收机信号转换成中频信号;频率电压转换器（4），调谐到固定中频，用于转换中频信号相对的频率偏差 将固定的中频转换成相对于反射值的频率电压转换器（4）的输出信号的振幅变化，用于导出可控振荡器的可变电容二极管（D）的控制信号的控制信号生成电路（5） 6），其频率电压转换器（4）的输出信号至少部分地补偿非对称二极管电容 - 电压特性。 为了防止在该补偿期间发生不期望的侧调效应，可变电容二极管（D）的控制信号的频率相关变化是呈现在其中的最大值附近弯曲的不对称S曲线，并且其补偿 二极管电容变化的不对称性。

公开(公告)号：US4125863A

公开(公告)日：1978-11-14

申请号：US832005

申请日：1977-09-09

申请人： Rangaswamy Arumugham

发明人： Rangaswamy Arumugham

IPC分类号： H03J7/10 ,  H04N5/50 ,  H04B1/16

CPC分类号： H03J7/10 ,  H04N5/50

摘要： Automatic frequency control (AFC) circuitry compensating for the nonlinear tuning voltage sensitivity characteristics of voltage-controlled tuners is shown. The circuit uses a nonlinear device, such as a zener diode, to develop an amount of error correction voltage that increases with increasing tuning voltage. In addition, through the use of a VHF Bandswitch voltage, the circuit controls an impedance in a network that combines the tuning voltage with the voltage developed by the AFC system in response to tuning errors. As a result, a greater amount of AFC error correction voltage is developed on Low Band VHF channels than on High Band channels. In this manner, substantially constant AFC pull-in range is maintained both within and among High and Low Band VHF and UHF channels.

摘要翻译： 示出了补偿压控调谐器的非线性调谐电压灵敏度特性的自动频率控制（AFC）电路。 该电路使用诸如齐纳二极管的非线性器件来开发随调谐电压的增加而增加的纠错电压量。 此外，通过使用VHF频带开关电压，该电路控制网络中的阻抗，其将调谐电压与由AFC系统开发的电压响应于调谐误差组合。 结果，在低频VHF通道上比在高频带通道上产生更大量的AFC纠错电压。 以这种方式，在高频和低频VHF和UHF频道内部和之间都保持基本上恒定的AFC拉入范围。