Advanced Qualification · A-005 Transmitters, modulation and processing · A-005-004-006
What kind of input signal is used to test the amplitude linearity of a single-sideband phone transmitter while viewing the output on an oscilloscope?
- A An audio-frequency square wave
- B Normal speech
- C Two audio-frequency sine waves
- D An audio-frequency sine wave
Correct answer: C — Two audio-frequency sine waves. From the official ISED question bank, verified word for word.
Why
To test amplitude linearity in a single-sideband transmitter, you need two audio-frequency sine waves because they create a predictable pattern on an oscilloscope that reveals if the amplifier distorts the signal. The full explanation — and one for every question — is in Pro.
Practise this section
Transmitters, modulation and processing: AM, FM, SSB, keying, speech processing, and the numbers behind occupied bandwidth.