What is the term that describes a device's ability to amplify a signal?
The correct answer is Gain. Gain is the term that describes a device's ability to amplify a signal - the ratio of output signal strength to input signal strength. Gain can be expressed in decibels (dB) or as a simple ratio. For example, a gain of 20 dB means the output is 10 times stronger than the input. Gain is a fundamental concept in electronics, describing how much a signal is increased by an amplifier, transistor, or other active device. For amateur radio operators, understanding gain is essential when working with amplifiers, receivers, transmitters, and antenna systems. Different types of gain include voltage gain, current gain, and power gain, all describing different aspects of signal amplification.
Exam Tip
Gain = amplification. If the question asks about a device's ability to amplify, the answer is 'gain.' The other options are resistance-related terms that describe power loss, not signal increase.
Memory Aid
"Gain = amplification ability. Think 'G'ain = 'G'rowth of signal. More gain = stronger output signal. Resistance terms describe loss, not gain."
Real-World Application
Your RF amplifier might have a gain of 20 dB, meaning it multiplies the input signal strength by 100 times. A weak 1-milliwatt signal from your antenna becomes a 100-milliwatt signal after amplification. This gain makes weak signals strong enough to be processed and heard. Understanding gain helps you select appropriate amplifiers and predict system performance.
Key Concepts
Why Other Options Are Wrong
Option B (Forward resistance): Incorrect. Forward resistance is a property of diodes, describing the resistance when forward-biased. It's not related to amplification or gain.
Option C (Forward voltage drop): Incorrect. Forward voltage drop is the voltage required for a diode to conduct, typically 0.6-0.7V for silicon diodes. It's not related to signal amplification.
Option D (On resistance): Incorrect. On resistance refers to the resistance of a switch or transistor when it's turned on (conducting). It describes power loss, not amplification capability.
题目解析
The correct answer is Gain. Gain is the term that describes a device's ability to amplify a signal - the ratio of output signal strength to input signal strength. Gain can be expressed in decibels (dB) or as a simple ratio. For example, a gain of 20 dB means the output is 10 times stronger than the input. Gain is a fundamental concept in electronics, describing how much a signal is increased by an amplifier, transistor, or other active device. For amateur radio operators, understanding gain is essential when working with amplifiers, receivers, transmitters, and antenna systems. Different types of gain include voltage gain, current gain, and power gain, all describing different aspects of signal amplification.
考试技巧
Gain = amplification. If the question asks about a device's ability to amplify, the answer is 'gain.' The other options are resistance-related terms that describe power loss, not signal increase.
记忆口诀
Gain = amplification ability. Think 'G'ain = 'G'rowth of signal. More gain = stronger output signal. Resistance terms describe loss, not gain.
实际应用示例
Your RF amplifier might have a gain of 20 dB, meaning it multiplies the input signal strength by 100 times. A weak 1-milliwatt signal from your antenna becomes a 100-milliwatt signal after amplification. This gain makes weak signals strong enough to be processed and heard. Understanding gain helps you select appropriate amplifiers and predict system performance.
错误选项分析
Option B (Forward resistance): Incorrect. Forward resistance is a property of diodes, describing the resistance when forward-biased. It's not related to amplification or gain. Option C (Forward voltage drop): Incorrect. Forward voltage drop is the voltage required for a diode to conduct, typically 0.6-0.7V for silicon diodes. It's not related to signal amplification. Option D (On resistance): Incorrect. On resistance refers to the resistance of a switch or transistor when it's turned on (conducting). It describes power loss, not amplification capability.
知识点
Gain, Amplification, Signal amplification, Amplifier characteristics
Verified Content
Question from official FCC Technician Class question pool. Explanation reviewed by licensed amateur radio operators.