Ace the ARRL Technician Exam 2025 – Tune In and Transmit Your Success!

The correct choice is double sideband. Double sideband amplitude modulation (DSBAM) is a form of amplitude modulation where the carrier signal is modulated in amplitude with the information signal, resulting in two sidebands. This method transmits the entire amplitude of the modulating audio signal, enabling the receiver to extract the information by demodulating both the upper and lower sidebands of the carrier frequency.

Single sideband is a derivative of double sideband that retains only one of the sidebands, which is more efficient for bandwidth usage but is not a complete form of amplitude modulation like double sideband.

Frequency modulation and phase modulation, while also forms of modulation, operate differently by varying the frequency or phase of the carrier wave rather than its amplitude, thereby excluding them from being classified as amplitude modulation forms.