Usage of VHF and UHF bands in Ham Radio
The Very High Frequency (VHF, 30–300 MHz) and Ultra High Frequency (UHF, 300–3000 MHz) bands play a crucial role in amateur radio, offering reliable short-to-medium-range communication. Initially underutilized, they gained popularity after World War II with surplus military equipment and technological advancements. Today, these bands are widely used for local, emergency, and experimental communication.
Origins in Ham Radio
Initially, most ham radio operators worked in the High Frequency (HF) bands, but as technology improved, the FCC and other regulatory bodies allocated sections of the VHF and UHF spectrum to amateur radio. The introduction of FM (frequency modulation) and repeaters in the mid-20th century greatly expanded their use, making them popular for local and regional communication.
Today, common ham bands include:
- VHF: 6 meters (50-54 MHz), 2 meters (144-148 MHz)
- UHF: 70 centimeters (420-450 MHz), 33 centimeters (902-928 MHz)
Propagation characteristics
Unlike HF bands, which rely on ionospheric reflection for long-distance communication, VHF and UHF signals primarily travel via line-of-sight (LOS). However, several techniques extend their range:
- Tropospheric Ducting & Scattering – Temperature inversions or atmospheric conditions allow signals to travel hundreds of miles.
- Sporadic-E (Es) – Ionized patches in the E-layer reflect VHF signals over 600–1500 miles, mainly on 6m and sometimes on 2m.
- Meteor Scatter – Signals reflect briefly off ionized meteor trails, useful for 6m and 2m digital modes like MSK144.
- Aurora Reflection – Strong auroral activity scatters signals, especially in 50 MHz and 144 MHz bands.
- Moonbounce (EME) – Signals bounce off the Moon’s surface, enabling worldwide communication with high-gain antennas.
- Satellite Communication (AMSAT/OSCAR) – Amateur satellites relay signals, extending range globally.
Common modes and techniques
- FM & Repeaters – The most common method for local VHF/UHF communication, often linked over large regions.
- Digital Voice (D-STAR, DMR, System Fusion) – Provides clearer audio, messaging, and internet-linked networks.
- APRS & Packet Radio – Used for tracking, text messaging, and data exchange, mainly on 144.390 MHz.
- Weak-Signal Modes (SSB, CW, FT8, MSK144) – Used for long-distance VHF/UHF DXing, meteor scatter, and EME.
- Mesh Networks & Data Links – Broadband-Hamnet and AREDN create digital emergency communication networks over UHF bands.
VHF and UHF bands are not just for local chat or repeater use—they offer a vast range of exciting propagation methods and digital technologies. From bouncing signals off meteors and the Moon to linking repeaters across the globe with the internet, these bands play a crucial role in emergency communications, experimentation, and technical advancements in ham radio. Whether you’re working satellites, chasing distant DX on 6m, or experimenting with digital mesh networks, VHF and UHF remain some of the most dynamic parts of amateur radio.
The VHF and UHF bands are more than just local communication channels—they offer exciting propagation methods and advanced digital technologies. Whether bouncing signals off meteors, working satellites, or experimenting with mesh networks, these bands remain vital in modern ham radio for emergency response, DXing, and technical innovation.