Understanding International Frequency Allocations for Shortwave DXing
Recent Trends
In the past several years, international spectrum management bodies have reviewed portions of the shortwave bands—particularly the 7 MHz, 9 MHz, and 11 MHz ranges—to accommodate growing demand from digital broadcasting and emergency communication services. Some national regulators have begun reallocating marginal frequencies previously reserved for broadcasting to fixed and mobile services. At the same time, listener reports indicate a gradual reduction in the number of high-power broadcasters using traditional 49-meter and 31-meter bands, especially during local daytime hours.
Amateur radio operators and DX listeners have noted increased co-channel interference as stations shrink their schedules and consolidate onto fewer frequencies. The trend toward spectrum sharing, rather than exclusive broadcasting allocations, continues to shape the shortwave landscape.
Background
Shortwave frequencies are divided into allocated bands at World Radiocommunication Conferences (WRCs) held by the International Telecommunication Union. For decades, bands such as 49 m (5.9–6.2 MHz), 41 m (7.1–7.3 MHz), 31 m (9.4–9.9 MHz), 25 m (11.6–12.1 MHz), and 22 m (13.5–13.8 MHz) were primarily reserved for international broadcasting. Amateur radio operates on separate but adjacent allocations, e.g., 7.0–7.2 MHz (40 m) and 14.0–14.35 MHz (20 m).
- Broadcasting allocations are generally shared among nations under bilateral coordination.
- Secondary services (e.g., time signals, aeronautical, maritime) have priority in certain segments, limiting DX-friendly transmissions.
- ITU regions (1, 2, 3) have different band plans, affecting which frequencies carry programming in different parts of the world.
User Concerns
DX listeners face several practical challenges tied to frequency allocation changes:
- Fewer dedicated broadcasting frequencies mean more competition among stations, increasing interference and reducing clarity.
- Some popular DX bands (e.g., 90 m for tropical band enthusiasts) have been partially reclassified for local broadcasting or digital services, shrinking usable spectrum.
- Listeners using older receivers may not be able to fine-tune narrow digital transmissions or follow frequency changes announced only on websites.
- Inconsistent seasonal and solar-cycle propagation makes it difficult to rely on a fixed list of active frequencies; allocation shifts compound this uncertainty.
Likely Impact
The ongoing adjustments will affect different listener groups in varying ways:
| Listener Type | Projected Impact |
|---|---|
| Casual DX enthusiasts | May find fewer easily audible stations during evening hours; may need to explore less crowded edges of bands. |
| Serious DXers with good antennas | Can still exploit DX windows during periods of favorable propagation, but will require more frequent checking of frequency schedules. |
| Loggers & QSL collectors | May need to monitor digital modes (e.g., DRM) and utility stations that occupy former broadcast allocations, altering traditional logging categories. |
| Newcomers to shortwave | Might encounter greater frustration due to band congestion and fewer consistent signals; introductory guides should emphasize using SDRs and online resources to stay current. |
Overall, the hobby is likely to become more technical and schedule-dependent, shifting emphasis from passive listening to active frequency hunting.
What to Watch Next
Several developments will shape the near-term future of shortwave frequency allocations for DX listeners:
- The next WRC (planned for 2027) will consider proposals to repurpose parts of the 26 MHz and 28 MHz ranges—currently used by amateurs and some broadcasters—for mobile broadband. DX listeners should monitor preparatory documents from their national administrations.
- Increased use of single-sideband (SSB) by international broadcasters may offer reduced interference but requires receivers with SSB capability, something still absent in many consumer portables.
- Regional coordination groups (e.g., the High Frequency Coordination Conference) are pressured to minimize overlap in crowded bands; their monthly bulletins are a useful tool for serious DXers.
- The growth of software-defined radio (SDR) networks, such as KiwiSDR and WebSDR, allows listeners to remotely tune vacant frequencies that local propagation might otherwise mask—a trend that could outlast many allocation changes.
DX listeners are advised to bookmark the ITU’s update page and national regulator websites, and to participate in forums where frequency changes are shared in real time. Adapting to new allocations is a matter of vigilance rather than abandonment of the hobby.