FCC E7H - 实用射频电路与滤波器

#E7H01🔗

What are three common oscillator circuits?

常见的振荡电路有哪三种？

Taft, Pierce, and negative feedback

塔夫脱、皮尔斯和负面反馈

Pierce, Fenner, and Beane

皮尔斯、芬纳和比恩

Taft, Hartley, and Pierce

塔夫脱、哈特利和皮尔斯

Colpitts , Hartley, and Pierce

科尔皮茨、哈特利和皮尔斯

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#E7H02🔗

What is a microphonic?

什么是麦克风？

An IC used for amplifying microphone signals

用于放大麦克风信号的IC

Distortion caused by RF pickup on the microphone cable

麦克风电缆上的射频拾音造成的失真

Changes in oscillator frequency caused by mechanical vibration

机械振动引起的振荡器频率变化

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Excess loading of the microphone by an oscillator

振荡器对麦克风造成过度负载

#E7H03🔗

What is a phase-locked loop?

什么是锁相环？

An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator

由比率检测器、电抗调制器和压控振荡器组成的电子伺服环路

An electronic circuit also known as a monostable multivibrator

也称为单稳态多谐振荡器的电子电路

An electronic servo loop consisting of a phase detector, a low - pass filter , a voltage-controlled oscillator, and a stable reference oscillator

由鉴相器、低通滤波器、压控振荡器和稳定参考振荡器组成的电子伺服环路

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An electronic circuit consisting of a precision push-pull amplifier with a differential phase input

由具有差分相位输入的精密推挽放大器组成的电子电路

#E7H04🔗

How is positive feedback supplied in a Colpitts oscillator?

科尔皮兹振荡器如何提供正反馈？

Through a tapped coil

通过抽头线圈

Through link coupling

通过链接耦合

Through a capacitive divider

通过电容分压器

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Through a neutralizing capacitor

通过中和电容器

#E7H05🔗

How is positive feedback supplied in a Pierce oscillator?

皮尔斯振荡器如何提供正反馈？

Through a tapped coil

通过抽头线圈

Through link coupling

通过链接耦合

Through a neutralizing capacitor

通过中和电容器

Through a quartz crystal

通过石英晶体

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#E7H06🔗

Which of these functions can be performed by a phase-locked loop?

锁相环可以执行以下哪些功能？

Wide-band AF and RF power amplification

宽带 AF 和 RF 功率放大

Frequency synthesis and FM demodulation

频率合成和FM解调

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Photovoltaic conversion and optical coupling

光伏转换与光耦合

Comparison of two digital input signals and digital pulse counting

两个数字输入信号的比较和数字脉冲计数

#E7H07🔗

How can an oscillator’s microphonic responses be reduced?

如何降低振荡器的颤噪响应？

Use NP0 capacitors

使用NP0电容

Reduce noise on the oscillator’s power supply

降低振荡器电源的噪声

Increase the gain

增加增益

Mechanically isolate the oscillator circuitry from its enclosure

将振荡器电路与其外壳机械隔离

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#E7H08🔗

Which of the following components can be used to reduce thermal drift in crystal oscillators?

以下哪些元件可用于减少晶体振荡器的热漂移？

NP0 capacitors

NP0电容

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Toroidal inductors

环形电感器

Wirewound resistors

线绕电阻器

Non-inductive resistors

无感电阻

#E7H09🔗

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital-to-analog converter, and a low-pass anti-alias filter?

什么类型的频率合成器电路使用相位累加器、查找表、数模转换器和低通抗混叠滤波器？

A direct digital synthesizer

直接数字合成器

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A hybrid synthesizer

混合合成器

A phase-locked loop synthesizer

锁相环合成器

A direct conversion synthesizer

直接转换合成器

#E7H10🔗

What information is contained in the lookup table of a direct digital synthesizer (DDS)?

直接数字合成器 (DDS) 的查找表中包含哪些信息？

The phase relationship between a reference oscillator and the output waveform

参考振荡器与输出波形之间的相位关系

Amplitude values that represent the desired waveform

代表所需波形的幅度值

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The phase relationship between a voltage-controlled oscillator and the output waveform

压控振荡器与输出波形之间的相位关系

Frequently used receiver and transmitter frequencies

常用的接收器和发射器频率

#E7H11🔗

What are the major spectral impurity components of direct digital synthesizers?

直接数字合成器的主要频谱杂质成分有哪些？

Broadband noise

宽带噪声

Digital conversion noise

数字转换噪声

Spurious signals at discrete frequencies

离散频率的杂散信号

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Harmonics of the local oscillator

本地振荡器的谐波

#E7H12🔗

Which of the following ensures that a crystal oscillator operates on the frequency specified by the crystal manufacturer?

以下哪一项可确保晶体振荡器按照晶体制造商指定的频率运行？

Provide the crystal with a specified parallel inductance

为晶体提供指定的并联电感

Provide the crystal with a specified parallel capacitance

为晶体提供指定的并联电容

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Bias the crystal at a specified voltage

在指定电压下对晶体施加偏置

Bias the crystal at a specified current

以指定电流偏置晶体

#E7H13🔗

Which of the following is a technique for providing highly accurate and stable oscillators needed for microwave transmission and reception?

以下哪项是提供微波传输和接收所需的高精度和稳定振荡器的技术？

Use a GPS signal reference

使用 GPS 信号参考

Use a rubidium stabilized reference oscillator

使用铷稳定参考振荡器

Use a temperature-controlled high Q dielectric resonator

使用温控高Q介质谐振器

All these choices are correct

所有这些选项都是正确的

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FCC E7H - 实用射频电路与滤波器

小节 E7H：实用射频电路与滤波器