Deep Dive: G4E07
The correct answer is D: All these choices are correct. What may cause receive interference to an HF transceiver installed in a vehicle includes: the battery charging system, the fuel delivery system, and the control computers. All three can generate electrical noise that interferes with HF reception. For amateur radio operators, this explains common mobile interference sources. Understanding this helps when troubleshooting mobile interference.
Why Other Answers Are Wrong
Option A: While correct, this is incomplete. Fuel delivery system and control computers also cause interference. Option B: While correct, this is incomplete. Battery charging system and control computers also cause interference. Option C: While correct, this is incomplete. Battery charging system and fuel delivery system also cause interference.
Exam Tip
All three can cause mobile receive interference: battery charging system, fuel delivery system, control computers. When all listed systems can cause interference to mobile HF transceivers, 'all of the above' is usually the answer. All generate electrical noise.
Memory Aid
All three can cause interference: Battery charging, Fuel delivery, Control computers. Think 'A'll 'V'ehicle 'S'ystems can cause interference. All three generate electrical noise that interferes with HF reception. Common mobile interference sources.
Real-World Example
Your HF mobile transceiver experiences interference. Investigation reveals: (1) Battery charging system (alternator) generates noise, (2) Fuel delivery system (fuel pump, injectors) generates noise, (3) Control computers (ECU, various modules) generate noise. All three systems can cause interference to HF reception.
Source & Coverage
Question Pool: 2023-2027 Question Pool
Subelement: G4E
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 G4E topic.