Goal of this stage: know where to tune before you touch the dial. Shortwave is not random. It follows the sun.
2.1 Switch your clock to UTC
Every schedule, log and station announcement in this hobby uses Coordinated Universal Time. Set a second clock to UTC and use it for everything. To check accuracy, tune a time station: WWV in Fort Collins, Colorado, transmits on 2.5, 5, 10, 15 and 20 MHz; WWVH on Kauai, Hawaii, shares most of those frequencies; CHU in Ottawa uses 3330, 7850 and 14670 kHz. These are also excellent test signals for your antenna.
2.2 Learn the broadcast bands
International broadcasters cluster in bands named by wavelength in metres. Approximate ranges:
| Band | Range (MHz) | Best time |
|---|---|---|
| 49 m | 5.90–6.20 | Night, regional and long-haul |
| 41 m | 7.20–7.45 | Evening and night |
| 31 m | 9.40–9.90 | Evening, often all night |
| 25 m | 11.60–12.10 | Day and early evening |
| 19 m | 15.10–15.80 | Daytime |
| 16 m | 17.48–17.90 | Daytime, solar maximum |
| 13 m | 21.45–21.85 | Midday, high solar activity |
2.3 Apply the day-night rule
Simple rule: high frequencies by day, low frequencies by night. The reason is the ionosphere. In daylight, the sun charges the upper F layers so they reflect higher frequencies, while the low D layer absorbs lower ones. After sunset the D layer fades quickly, lower bands open up, and the F layers can no longer support the highest frequencies. So: 19 m and 16 m at lunch, 41 m and 49 m after dark, 31 m as the bridge between.
2.4 Watch the grey line
The grey line is the band of twilight circling the Earth. Signals travelling along it often arrive unusually strong, because the absorbing D layer is weak on both ends while the reflecting layers are still active. Listen in the half hour around your local sunrise and sunset. Many listeners log their rarest stations here.
2.5 Read the space weather
The sun runs in roughly 11-year cycles. Solar Cycle 25 reached its maximum period around 2024–2025, according to NOAA and NASA, and higher bands have been unusually lively. Three numbers matter, all published by the NOAA Space Weather Prediction Center in Boulder, Colorado:
- Solar flux index (SFI) — higher means higher bands are more likely open.
- K-index — geomagnetic disturbance, 0 to 9. Low is good. A high K-index degrades signals, especially on polar paths.
- Radio blackouts — solar flares can wipe the daytime bands for minutes to hours.
If a band is dead and the K-index is high, it is not your radio.
2.6 Track the seasonal schedules
Broadcasters change frequencies twice a year. The A season starts on the last Sunday of March; the B season starts on the last Sunday of October. The High Frequency Coordination Conference (HFCC) coordinates many of these schedules under the framework of the ITU. Check your references after each change.
Checkpoint
You are ready for stage 03 when you can predict, before switching on, which band should carry signals at your current UTC time. Now you will find signals you cannot name. Stage 03 names them.