A radio propagation beacon
is a radio beacon
, whose purpose is the investigation of the propagation
of radio signals. Most radio propagation beacons use amateur radio
frequencies. They can be found on HF
, and microwave
frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers.
Most beacons operate in continuous wave (A1A) and transmit their identification (call sign and location). Some of them send long dashes to facilitate signal stength measurement. A small number of beacons transmit Morse code by frequency modulation (F1A). A few beacons transmit signals in digital modulation modes, like radioteletype (F1B) and PSK31 (G1B).
160 meters beacons
The International Amateur Radio Union Region 2 (North and South America) bandplan reserves the range 1999 kHz to 2000 kHz for propagation beacons.
10 meters beacons
Most high frequency radio propagation beacons are found in the 10 meters (28 MHz) frequency band, where they are good indicators of Sporadic E ionospheric propagation. According to IARU bandplans, the following 28 MHz frequencies are allocated to radio propagation beacons:
| IARU Region
|| Beacon allocations |
- 28190-28199 Regional Time Shared
- 28199-28201 WW Time Shared
- 28201-28225 Continuous Duty
- 28190-28199 Regional Time Shared
- 28199-28201 IBP/NCDXF
- 28201-28225 Beacons, continuous duty
- 28225-28300 Shared
6 meters beacons
In the 6 meters
(50 MHz) band, beacons operate in the lower part of the band, in the range 50000 kHz to 50080 kHz. The American Radio Relay League
bandplan recommends 50060 to 50080 kHz for beacons in the United States
. Due to unpredictable and intermittent long distance propagation, usually achieved by a combination of ionospheric conditions, beacons are very important in providing early warning for 50 MHz openings.
Beacons on 144 MHz and higher frequencies are mainly used to identify tropospheric radio propagation openings. It is not uncommon for VHF and UHF beacons to use directional antennas. Frequency allocations for beacons on VHF and UHF bands vary widely in different IARU regions and countries. The current allocation in the United Kingdom, which also reflects IARU Region 1 recommendations, is the following:
|| Beacon allocation (kHz) |
| 4 m
|| 70,000-70,030 |
| 2 m
|| 144,400-144,490 |
| 70 cm
|| 432,800-432,990 |
| 23 cm
|| 1296,800-1296,990 |
Most radio propagation beacons are operated by individual radio amateurs or amateur radio societies and clubs. As a result, there are frequent additions and deletions to the lists of beacons. There are, however a few major projects coordinated by organizations like the International Telecommunications Union and the International Amateur Radio Union.
IARU Beacon Project
The International Beacon Project (IBP), which is coordinated by the Northern California DX Foundation and the International Amateur Radio Union, consists of 18 HF propagation beacons worldwide, which transmit in turns on 14100 kHz, 18110 kHz, 21150 kHz, 24930 kHz, and 28200 kHz.
ITU sponsored beacons
As part of an International Telecommunications Union-funded project, radio propagation beacons were installed by national authorities at Sveio, Norway (callsign LN2A, ) and at Darwin, Australia (callsign VL8IPS, ). The beacons operated on frequencies 5471.5 kHz, 7871.5 kHz, 10408.5 kHz, 14396.5 kHz, and 20948.5 kHz.. Since 2002, there have been no reception reports for these beacons and the relevant ITU web pages have been removed.
DARC beacon project
The Deutscher Amateur-Radio-Club
sponsors two beacons which transmit from Scheggerott
, near Kiel
(). These beacons are DRA5 on 5195 kHz and DK0WCY on 10144 kHz. In addition to identification and location, every 10 minutes these
beacons transmit solar and geomagnetic
bulletins. Transmissions are in Morse code for aural reception, RTTY and PSK31.
RSGB 5 MHz beacon project
The Radio Society of Great Britain
operates three radio propagation beacons on 5290 kHz, which transmit in sequence, for one minute each, every 15 minutes. The project includes GB3RAL near Didcot
GB3WES in Cumbria
and GB3ORK in the Orkney Islands
(). GB3RAL, which is located at the Rutherford-Appleton Laboratory, also transmits continuously on 28215 kHz and on a number of low VHF frequencies (40050, 50053, 60053 and 70053 kHz).
Notes and References
- IARU/NDXF International Beacon Project
- R.Wilkinson, G6GVI; S.Cooper, GM4AFF; B. Hansen, OZ2M The 70 MHz Beacon List. The Four Metres Website. Retrieved on 2008-04-27..
- Martin Harrison, G3USF Worldwide List of HF Beacons. Retrieved on 2008-04-27..
- Martin Harrison, G3USF Worldwide List of 50 Beacons. Retrieved on 2008-04-27..
- Joost Schuitemaker, ZS5S List of active HF Amateur Radio Beacons. Retrieved on 2008-04-27..
- Joost Schuitemaker, ZS5S Additional HF Beacon Information. Retrieved on 2008-04-27..
- Joost Schuitemaker, ZS5S Inactive HF Beacons. Retrieved on 2008-04-27..
- Thomas M. Rösner, DL8AAM The DL8AAM QSL Collection: QSLs from Radio Beacons. Retrieved on 2008-01-05..
- John Jaminet, W3HMS and Charlie Heisler, K3VDB (2007). "Bulding a beacon for 2401 MHz". CQ VHF 10 (3): 44–46.
- Andrew Talbot, G4JNT Design and building of the 5 MHz beacons, GB3RAL, GB3WES and GB3ORK. Retrieved on 2008-02-13..
- Andy Talbot, G4JNT The Next Generation of Beacons for the 21st century. Retrieved on 2008-03-16..
- UK Amateur Radio & Microwave Beacons. UK Microwave Groups (UKMuG). Retrieved on 2008-04-27..