International Broadcast Bands
The bands and frequencies below are derived from multiple sources, and different radios may have different frequency numbers. Most international broadcasters use amplitude modulation with 5 kHz steps between channels; a few use single sideband modulation. The World Radiocommunication Conference (WRC), organized under the auspices of the International Telecommunication Union, allocates bands for various services in periodic conferences. The last WRC took place in 2007. At WRC-97 in 1997, the following bands were allocated for international broadcasting:
| Band | Frequency Range | Remarks |
|---|---|---|
| 120 m | 2300 - 2495 kHz | Tropical (regional) band |
| 90 m | 3200–3400 kHz | Tropical band |
| 75 m | 3900–4000 kHz | Shared with the North American amateur radio 80 m band |
| 60 m | 4750–5060 kHz | Tropical band |
| 49 m | 5900–6200 kHz | |
| 41 m | 7200–7450 kHz | Shared with the amateur radio 40 m band |
| 31 m | 9400–9900 kHz | Most heavily used band |
| 25 m | 11,600–12,100 kHz | |
| 22 m | 13,570–13,870 kHz | Substantially used in Eurasia |
| 19 m | 15,100–15,800 kHz | |
| 16 m | 17,480–17,900 kHz | |
| 15 m | 18,900–19,020 kHz | Lightly utilized; may become DRM band in future |
| 13 m | 21,450–21,850 kHz | |
| 11 m | 25,600–26,100 kHz | May be used for local DRM broadcasting |
- 120 m band – Mostly used locally in tropical regions, with time stations at 2500 kHz. Although this is regarded as shortwave, it is in the MF band.
- 90 m band – Mostly used locally in tropical regions, with limited long-distance reception at night
- 75 m band – Mostly used in the Eastern Hemisphere; not widely received in North and South America
- 60 m band – Mostly used locally in tropical regions, although widely usable at night. Time stations use 5000 kHz.
- 49 m band – Good year-round night band; daytime reception poor
- 41 m band – Reception varies by region – reasonably good night reception, but few transmitters in this band target North America. According to the WRC-03 Decisions on HF broadcasting, in International Telecommunication Union regions 1 and 3, the segment 7100–7200 kHz is reserved for amateur radio use and there are no new broadcasting allocations in this portion of the band. 7350–7400 kHz is newly allocated; in Regions 1 and 3, 7400–7450 kHz was also allocated effective March 29, 2009.
- 31 m band – Good year-round night band; seasonal during the day, with best reception in winter. Time stations are clustered around 10 MHz.
- 25 m band – Generally best during summer and the period before and after sunset year-round
- 22 m band – Similar to the 19 m band; best in summer
- 19 m band – Day reception good, night reception variable; best during summer. Time stations such as WWV use 15 MHz.
- 16 m band – Day reception good; night reception varies seasonally, with summer best.
- 15 m band – Seldom used
- 13 m band – Erratic daytime reception, with very little night reception. Similar to 11 metres, but long-distance daytime broadcasting keeps this band active in the Asia-Pacific region.
- 11 m band – Seldom used. Daytime reception poor low in the solar cycle, but potentially excellent when the solar cycle (generally indicated by the number of sunspots) is high. Nighttime reception nonexistent, except for local groundwave propagation. Digital Radio Mondiale has proposed that this band be used for local digital shortwave broadcasts, testing the concept in Mexico City in 2005. The Citizens' Band allocation in most countries is within this band.
Read more about this topic: Shortwave Bands
Famous quotes containing the words broadcast and/or bands:
“Listening to a news broadcast is like smoking a cigarette and crushing the butt in the ashtray.”
—Milan Kundera (b. 1929)
“The thing that struck me forcefully was the feeling of great age about the place. Standing on that old parade ground, which is now a cricket field, I could feel the dead generations crowding me. Here was the oldest settlement of freedmen in the Western world, no doubt. Men who had thrown off the bands of slavery by their own courage and ingenuity. The courage and daring of the Maroons strike like a purple beam across the history of Jamaica.”
—Zora Neale Hurston (1891–1960)