Which of the following correctly identifies the potential consequence of operating the HF radio at high power?

• A. Antenna damage
• B. GPS signal disruption
• C. Electromagnetic Interference (EMI) may occur
• D. Fuel system fault

Answer: (C)

High-power HF transmissions emit strong RF energy that can couple into nearby electronics and wiring, creating electromagnetic interference. This EMI is the broad consequence of transmitting at high power and can show up as noise or degraded performance across avionics, including navigation systems and GPS receivers. In other words, the risk isn’t a specific system fault by itself but the interference that can disturb other equipment.

Antenna damage isn’t the typical outcome unless you exceed design ratings or have a fault in the feed, which isn’t the general consequence of normal high-power operation. GPS disruption is a possible result of EMI, but it’s a specific manifestation of EMI rather than the primary consequence itself. Fuel system faults have no direct relation to RF energy.