Subelement M: M – Communications Technology— Topic 82: Types of Transmissions
Question 3-82M5
Element 3 (GROL)Which of the following statements about SSB voice transmissions is correct?
Explanation
SSB voice transmissions normally use **J3E emissions**. This emission designator signifies a single sideband with a suppressed carrier. In SSB, the audio signal modulates a carrier, producing two sidebands and the original carrier. To achieve efficiency, one sideband is filtered out, and the carrier is significantly reduced or eliminated before transmission. This saves both bandwidth and power.
A) is incorrect because A3E describes Double Sideband Full Carrier Amplitude Modulation (AM), where both sidebands and the full carrier are transmitted.
B) is incorrect because F3E describes Frequency Modulation (FM) voice, a completely different modulation scheme from SSB.
D) is incorrect because A1A is the emission designator for unmodulated Continuous Wave (CW) Morse code, not voice, and its purpose isn't related to carrier suppression for SSB.
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