Deep Dive: E4A03
The correct answer is B: Spectrum analyzer. Which of the following test instruments is used to display spurious signals and/or intermodulation distortion products generated by an SSB transmitter is a spectrum analyzer. Spectrum analyzers show frequency domain, revealing spurious and IMD products. For amateur radio operators, this is important for transmitter testing. Understanding this helps when testing transmitters.
Why Other Answers Are Wrong
Option A (Differential resolver): Incorrect. Differential resolver isn't used - spectrum analyzer is used to display spurious and IMD. Differential resolver isn't the instrument. Option C (Logic analyzer): Incorrect. Logic analyzer isn't used - spectrum analyzer is used to display spurious and IMD. Logic analyzer isn't the instrument. Option D (Network analyzer): Incorrect. Network analyzer isn't typically used for this - spectrum analyzer is used to display spurious and IMD. Network analyzer isn't the instrument.
Exam Tip
Display spurious/IMD from SSB transmitter = spectrum analyzer. Think 'S'purious/'I'MD = 'S'pectrum 'I'nstrument. Spectrum analyzers show frequency domain, revealing spurious and IMD products. Not differential resolver, not logic analyzer, not network analyzer - just spectrum analyzer.
Memory Aid
Display spurious/IMD from SSB transmitter = spectrum analyzer. Think 'S'purious/'I'MD = 'S'pectrum analyzer. Spectrum analyzers show frequency domain, revealing spurious and IMD products. Important for transmitter testing.
Real-World Example
Testing an SSB transmitter: A spectrum analyzer is used to display spurious signals and/or intermodulation distortion products. The spectrum analyzer shows the frequency domain, making it easy to see unwanted signals at various frequencies. This is the instrument - spectrum analyzer for spurious and IMD display.
Source & Coverage
Question Pool: 2024-2028 Question Pool
Subelement: E4A
Reference: 2024-2028 Question Pool · E4 - Amateur Practices
Key Concepts
Verified Content
Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E4A topic.