Ham Amateur Radio Technician Practice Exam 2026 - Free Technician Practice Questions and Study Guide

In the VHF and UHF bands, upper sideband (USB) is the mode most commonly used for single sideband voice communications. This preference is primarily due to the characteristics of USB in providing more effective bandwidth usage and reducing interference. Upper sideband allows for clearer communications, especially under conditions where signals may be weaker or where multiple signals may be present.

Single sideband modulation, particularly USB, significantly reduces bandwidth compared to other modes, allowing for more operators to use the same frequency without overlapping. This efficiency is crucial in VHF and UHF bands, where space is limited and users often contend for the same channels.

The other modes listed, such as FM, tend to dominate in certain operational scenarios, particularly for local communications, but they are not as prevalent for long-distance voice communications in SSB. CW (Continuous Wave) is primarily used for Morse code transmissions, while lower sideband is less commonly employed at these frequencies for voice communication. Hence, upper sideband stands out as the preferred choice for SSB voice communication in these bands.