What factors affect the bandwidth of a transmitted CW signal?
IF bandwidth and Q
Modulation index and output power
Keying speed and shape factor (rise and fall time)✓Correct answer
All these choices are correct
Explanation
A CW signal is on-off keying, so its bandwidth comes from the keying envelope: faster sending shortens the elements and widens the spectrum, and abrupt rise and fall times add sidebands heard as key clicks. Receiver IF bandwidth and transmitter output power do not change what is actually radiated.