SignalPrep
Basic Qualification · B-003 Station assembly, practice and safety · B-003-004-006

In a basic CW transmitter, what does the key do?

  1. AIt switches the transmitted tone on and off
  2. BIt makes and breaks the antenna connection
  3. CIt switches the carrier on and off
  4. DIt switches the carrier between two frequencies

Correct answer: C — It switches the carrier on and off. From the official ISED question bank, verified word for word.

Why

In a basic CW (continuous wave) transmitter, the key acts as a simple switch that turns the radio frequency carrier signal on and off to create the dots and dashes of Morse code. The full explanation — and one for every question — is in Pro.

Practise this section

Station assembly, practice and safety is section B-003 of the Basic exam: Building a station safely: power supplies, grounding, RF exposure, lightning, feedline routing, and what a transmitter, receiver and transceiver actually do.

Drill B-003 — free, no account

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