Question T8D09
From subelement T8 - T8D
What is CW?
Why is this correct?
CW stands for Continuous Wave and is another name for Morse code transmission. The term originated to distinguish the clean, steady carrier waves of modern transmitters from the raspy, irregular signals produced by old spark-gap transmitters. Options A, B, and C are incorrect because CW is not a propagation method, not a digital mode for FM, and not related to coil winding techniques.
Memory tip
When you see 'CW' on amateur radio materials, always think 'Morse code.' The historical naming helps distinguish between transmission methods - the key pattern is that mode abbreviations often describe the technical characteristic of the signal rather than the information content being sent.
Learn more
CW operations require specific frequency privileges under Part 97, with Technician licensees having CW access on 80m, 40m, 15m, and 10m HF bands, plus all VHF/UHF/microwave allocations. CW signals occupy approximately 150 Hz bandwidth, making them extremely efficient for weak-signal communication. The narrow emission bandwidth allows more simultaneous contacts within a given frequency segment compared to voice modes.
Think about it
Why do you think amateur radio has preserved Morse code operation when digital modes can transmit text more efficiently?