Question T8A06
From subelement T8 - T8A
Which sideband is normally used for 10 meter HF, VHF, and UHF single-sideband communications?
Why is this correct?
Upper sideband (USB) is the standard for 10-meter HF, VHF, and UHF single-sideband communications. This is a widely adopted convention in amateur radio. Lower sideband (LSB) is used on frequencies below 10 MHz (160, 80, and 40 meter bands), while USB is used above 10 MHz including 10 meters and all VHF/UHF bands. The other options don't exist as standard sideband types in amateur radio.
Memory tip
Remember the '10 MHz dividing line' pattern: below 10 MHz uses LSB, above 10 MHz uses USB. This consistent convention helps ensure all operators use the same sideband for compatibility on each band.
Learn more
The USB/LSB convention exists because early SSB equipment had fixed sideband selection tied to frequency ranges. Using consistent sidebands across all operators on a band ensures compatibility—imagine the confusion if some stations transmitted USB while others used LSB on the same frequency! This standardization becomes critical during emergency communications and contests where quick, reliable contact establishment is essential for effective amateur radio operations.
Think about it
Why do you think amateur radio adopted different sideband conventions for different frequency ranges rather than using the same sideband everywhere?