FCC Exam Question: 3-86N1

What is a common occurrence when voice-testing an SSB aboard a boat?

A. Ammeter fluctuates down with each spoken word.
B. Voltage panel indicator lamps may glow with each syllable.
C. Automatic tuner cycles on each syllable.
D. Minimal voltage drop seen at power source.
Correct Answer: B

Explanation: Voice-testing an SSB aboard a boat often leads to voltage panel indicator lamps glowing or flickering with each syllable. This is due to RF (Radio Frequency) induction. The strong RF field from the SSB antenna and feedline can induce currents into nearby DC wiring runs, which effectively act as unintended antennas. These induced currents can cause low-power indicator lights (LEDs or small incandescent bulbs) to illuminate or glow in sync with the speech modulation, as RF power output fluctuates with each syllable. Option A is incorrect because an SSB transceiver draws *more* current during transmission peaks, so the ammeter would fluctuate *up*, not down. Option C is incorrect; an automatic tuner should find a match and hold it, not cycle on each syllable. Constant cycling indicates a problem with the tuner or antenna system. Option D is also incorrect; significant voltage drops can be a common problem with inadequate power wiring or battery capacity, so expecting a *minimal* drop isn't always realistic.

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Includes Elements 1, 3, 6, 7R, 8, and 9.