Question
What is the approximate bandwidth of a 13-WPM International Morse Code transmission?
Answer Options
- A) 13 Hz
- B) 26 Hz
- C) 52 Hz
- D) 104 Hz
Correct Answer: C
Explanation
The bandwidth of a CW (Morse Code) transmission is primarily determined by its keying speed (dots per second) and the rise and fall time (shape) of the transmitted pulse. Faster keying and sharper pulse shapes lead to wider bandwidth and potential key clicks.
The relationship between WPM and the minimum required bandwidth (BW) for a reasonably shaped pulse is approximately BW \approx 4 \times WPM. For a 13-WPM transmission, the approximate bandwidth is 4 \times 13 WPM = \mathbf{52 Hz}. This minimum bandwidth ensures that the signal is transmitted without excessive key clicks or spectral splatter on adjacent frequencies.
This topic was automatically created to facilitate community discussion about this exam question. Feel free to share study tips, memory tricks, or additional explanations!