Deep Dive: G4D09
The correct answer is B: 14.347 MHz to 14.350 MHz. The frequency range occupied by a 3 kHz USB signal with the displayed carrier frequency set to 14.347 MHz is 14.347 MHz to 14.350 MHz. USB uses the upper sideband, so the signal extends from carrier to (carrier + 3 kHz). For amateur radio operators, this helps understand SSB frequency ranges. Understanding this helps when operating SSB.
Why Other Answers Are Wrong
Option A: Incorrect. 14.347-14.647 MHz is way too wide - that's 300 kHz, not 3 kHz. USB extends only 3 kHz above carrier. Option C: Incorrect. 14.344-14.347 MHz would be LSB (lower sideband) - USB extends above the carrier, not below. Option D: Incorrect. 14.3455-14.3485 MHz is centered differently - USB extends from carrier to (carrier + 3 kHz), which is 14.347-14.350 MHz.
Exam Tip
3 kHz USB at 14.347 MHz = 14.347-14.350 MHz. Think 'U'SB = 'U'pper sideband = 'U'pper frequencies (carrier to carrier + 3 kHz). USB extends from 14.347 to (14.347 + 0.003) = 14.347-14.350 MHz. Not below carrier - above carrier.
Memory Aid
3 kHz USB at 14.347 MHz = 14.347-14.350 MHz. Think 'U'SB = 'U'pper sideband = 'U'pper frequencies. USB extends from carrier to (carrier + 3 kHz). Upper sideband uses frequencies above the carrier.
Real-World Example
You operate USB on 20 meters with carrier at 14.347 MHz. Your 3 kHz USB signal occupies 14.347-14.350 MHz (from carrier to carrier + 3 kHz). USB uses the upper sideband, so the signal extends above the carrier frequency. This is the USB frequency range.
Source & Coverage
Question Pool: 2023-2027 Question Pool
Subelement: G4D
Reference: 2023-2027 Question Pool · G4 - Amateur Radio Practices
Key Concepts
Verified Content
Question from the official FCC General Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the G4D topic.