Which precaution is recommended before powering up an aircraft radar transmitter for testing?

• A. Ensure the area in front of the antenna is clear of personnel.
• B. Make sure the receiver is shielded and grounded.
• C. Connect the transmitter to a matched load first.
• D. Check power supply voltages for safety.

Answer: (A)

Before energizing a radar transmitter, the most important safety step is to ensure the area directly in front of the antenna is clear of people. Aircraft radars emit high-power microwave energy in the direction of the beam, and anyone standing in that path can receive dangerous RF exposure or suffer eye and tissue injury. Establishing a cleared, controlled exclusion zone in front of the antenna protects personnel during testing. Other precautions, like connecting to a dummy load, shielding/grounding equipment, or checking power supplies, are important for general safe operation, but they do not address the immediate risk of exposure from the active antenna beam in the test area.