Advanced Qualification · A-005 Transmitters, modulation and processing · A-005-004-008
What audio frequencies are used in a two-tone test of the linearity of a single-sideband phone transmitter?
- AAny two audio tones may be used, but they must be within the transmitter audio passband, and must be harmonically
- BAny two audio tones may be used, but they must be within the transmitter audio passband, and should not be
- C20 Hz and 20 kHz tones must be used
- D1200 Hz and 2400 Hz tones must be used
Correct answer: B — Any two audio tones may be used, but they must be within the transmitter audio passband, and should not be. From the official ISED question bank, verified word for word.
Why
A two-tone test checks if a single-sideband transmitter distorts your voice by mixing signals together. The full explanation — and one for every question — is in Pro.
Practise this section
Transmitters, modulation and processing is section A-005 of the Advanced exam: Transmitters, modulation and processing: AM, FM, SSB, keying, speech processing, and the numbers behind occupied bandwidth.
Drill A-005 — free, no account