Ham Amateur Radio Technician Practice Exam 2026 – The Complete All-in-One Guide to Exam Success

Single sideband (SSB) is the correct answer because it uses the narrowest bandwidth among the listed phone emissions. SSB is a refinement of amplitude modulation (AM), where only one of the sidebands (either the upper or lower) is transmitted, while the carrier wave is suppressed. This results in a significant reduction of the bandwidth used for the transmission.

In contrast, amplitude modulation (AM) produces a wider bandwidth since it transmits both sidebands along with the carrier. Frequency modulation (FM) also occupies a wider bandwidth compared to SSB because it varies the frequency of the carrier signal, which creates a larger frequency spectrum for the same information. Continuous wave (CW) emissions use a different modulation method primarily for Morse code and technically don’t fall under phone emissions, but their bandwidth is constant and relatively narrow, yet still broader than SSB when considering voice communication.

SSB's efficient use of bandwidth allows for better signal quality and increased distance, making it a preferred method for voice communication in amateur radio.