FCC G7B - 实用的电路与原理图

#G7B01🔗

What is the purpose of neutralizing an amplifier?

放大器中和的目的是什么？

To limit the modulation index

限制调制指数

To eliminate self- oscillations

消除自振荡

✓ 正确答案

To cut off the final amplifier during standby periods

在待机期间切断末级放大器

To keep the carrier on frequency

保持载波在频率上

#G7B02🔗

Which of these classes of amplifiers has the highest efficiency?

这些类型的放大器中哪一类的效率最高？

Class A

A级

Class B

B级

Class AB

AB类

Class C

C级

✓ 正确答案

#G7B03🔗

Which of the following describes the function of a two-input AND gate?

以下哪项描述了两输入与门的功能？

Output is high when either or both inputs are low

当一个或两个输入都为低电平时，输出为高电平

Output is high only when both inputs are high

仅当两个输入均为高电平时输出才为高电平

✓ 正确答案

Output is low when either or both inputs are high

当一个或两个输入都为高电平时，输出为低电平

Output is low only when both inputs are high

仅当两个输入都为高电平时输出才为低电平

#G7B04🔗

In a Class A amplifier, what percentage of the time does the amplifying device conduct?

在 A 类放大器中，放大器件导通的时间百分比是多少？

100%

✓ 正确答案

More than 50% but less than 100%

大于 50% 但小于 100%

50%

Less than 50%

低于50%

#G7B05🔗

How many states does a 3-bit binary counter have?

3位二进制计数器有多少种状态？

✓ 正确答案

#G7B06🔗

What is a shift register?

什么是移位寄存器？

A clocked array of circuits that passes data in steps along the array

时钟电路阵列，沿着阵列逐步传递数据

✓ 正确答案

An array of operational amplifiers used for tri-state arithmetic operations

用于三态算术运算的运算放大器阵列

A digital mixer

数字调音台

An analog mixer

模拟混音器

#G7B07🔗

Which of the following are basic components of a sine wave oscillator?

以下哪些是正弦波振荡器的基本元件？

An amplifier and a divider

放大器和分频器

A frequency multiplier and a mixer

倍频器和混频器

A circulator and a filter operating in a feed-forward loop

在前馈环路中运行的循环器和滤波器

A filter and an amplifier operating in a feedback loop

在反馈环路中运行的滤波器和放大器

✓ 正确答案

#G7B08🔗

How is the efficiency of an RF power amplifier determined?

射频功率放大器的效率是如何确定的？

Divide the DC input power by the DC output power

将直流输入功率除以直流输出功率

Divide the RF output power by the DC input power

将射频输出功率除以直流输入功率

✓ 正确答案

Multiply the RF input power by the reciprocal of the RF output power

将射频输入功率乘以射频输出功率的倒数

Add the RF input power to the DC output power

将 RF 输入功率添加到 DC 输出功率

#G7B09🔗

What determines the frequency of an LC oscillator?

LC 振荡器的频率由什么决定？

The number of stages in the counter

计数器中的级数

The number of stages in the divider

分频器的级数

The inductance and capacitance in the tank circuit

储能电路中的电感和电容

✓ 正确答案

The time delay of the lag circuit

滞后电路的延时

#G7B10🔗

Which of the following describes a linear amplifier?

以下哪项描述了线性放大器？

Any RF power amplifier used in conjunction with an amateur transceiver

与业余收发器结合使用的任何射频功率放大器

An amplifier in which the output preserves the input waveform

输出保留输入波形的放大器

✓ 正确答案

A Class C high efficiency amplifier

C类高效放大器

An amplifier used as a frequency multiplier

用作倍频器的放大器

#G7B11🔗

For which of the following modes is a Class C power stage appropriate for amplifying a modulated signal?

C 类功率级适合放大调制信号，适用于以下哪种模式？

SSB

单边带

调频

✓ 正确答案

调幅

All these choices are correct

所有这些选项都是正确的

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FCC G7B - 实用的电路与原理图

小节 G7B：实用的电路与原理图