When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

توضیح

Lower sideband places the transmitted energy in roughly the 3 kHz below the displayed carrier frequency, so the carrier must sit at least 3 kHz above the lower band edge for the entire emission to stay inside the band. Carriers at the exact edge, 300 Hz above it, or 1 kHz above it all leave part of the sideband below the edge.