Amateur radio propagation beacon
An amateur 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 LF, MF, HF, VHF, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers.
The International Amateur Radio Union (IARU) and its member societies coordinate beacons established by radio amateurs.
Most beacons operate in continuous wave (A1A) and transmit their identification (call sign and location). Some of them send long dashes to facilitate signal strength measurement. A small number of beacons transmit Morse code by frequency shift keying (F1A). A few beacons transmit signals in digital modulation modes, like radioteletype (F1B) and PSK31 (G1B).
In the US, unattended beacons on frequencies lower than the 10-meter band are not legal.
Amateur experiments in the 2200-meter band (135.7–137.8 kHz) often involve operating temporary beacons.
In the United States and Canada, unlicensed experimenters ("LowFERs") establish low power beacons on radio frequencies between 160 kHz and 190 kHz.
Most high frequency radio propagation beacons are found in the 10-meter band (28 MHz), 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 Sub-bands (MHz)|
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 6-meter band (50 MHz) openings. Beacons operate in the lower part of the band, traditionally in the range 50.000 MHz to 50.080 MHz.
The IARU is encouraging individual beacons to move to 50.4 MHz to 50.5 MHz to assist with the establishment of the Synchronized Beacon Project. In the United States, the Federal Communications Commission (FCC) only permits unattended 6-meter beacon stations to operate between 50.060 and 50.080 MHz.
Several countries in ITU Region 1 have access to frequencies in the 70 MHz region, called the 4-meter band. The band shares many propagation characteristics with 6 meters. The preferred location for beacons is 70.000–70.090 MHz; however, in countries where this segment is not allocated to Amateur Radio, beacons may operate elsewhere in the band.
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. Frequencies set aside for beacons on VHF and UHF bands vary widely in different ITU regions and countries.
|Band||Beacon Sub-band (MHz)|
|ITU Region 1||ITU Region 2||ITU Region 3|
In addition to identifying propagation, microwave beacons are also used as signal sources to test and calibrate antennas and receivers. SHF beacons are not as common as beacons on the lower bands, and beacons above the 3-centimeter band (10 GHz) are unusual.
|Band||Beacon Sub-band (MHz)|
|ITU Region 1||ITU Region 2||ITU Region 3|
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 Amateur Radio Union (IARU).
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 high frequency propagation beacons worldwide, which transmit in turns on 14.100 MHz, 18.110 MHz, 21.150 MHz, 24.930 MHz, and 28.200 MHz.
DARC Beacon Project
The Deutscher Amateur-Radio-Club sponsors two beacons which transmit from Scheggerott, near Kiel ( JO44vq). 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. DK0WCY operates also a limited service beacon on 3579 kHz at 0720–0900 and 1600–1900 local time.
RSGB 5 MHz Beacon Project
The Radio Society of Great Britain operates a radio propagation beacon GB3ORK on 5290 kHz, transmitting every 15 minutes commencing at 2 minutes past the hour. It is located in the Orkney Islands ( IO89ja).
The GB3RAL VHF Beacon Cluster
GB3RAL, which is located at the Rutherford Appleton Laboratory, transmits continuously on a number of low-band and mid-band VHF frequencies – 40050, 50050, 60050 and 70050 kHz – as well as 28215 kHz in the 10-meter amateur band.
Weak Signal Propagation Reporter Network (WSPR)
A large-scale beacon project is underway using the WSPR transmission scheme included with the WSJT software suite. The loosely coordinated beacon transmitters and receivers, collectively known as the WSPRnet, report the real-time propagation characteristics of a number of frequency bands and geographical locations via the Internet. The WSPRnet website provides detailed propagation report databases and real-time graphical maps of propagation paths.
Synchronized Beacon Project
The Synchronized Beacon Project (SBP) is an effort to deploy coordinated beacon transmitters on 50 MHz using a one-minute transmitting sequence of PI4, CW, and unmodulated carrier. Since modern beacon transmitters are multi-mode and frequency-agile, beacons that normally transmit on other time-multiplexed modes such as WSPR can take part in the SBP when not transmitting in their primary mode. Beacons alternating between frequencies on the same band should sign CALL/S when transmitting on the SBP frequency to ensure unique entries in band-specific propagation report databases.
Notes and references
- Andy Talbot, G4JNT (May 2008). "Amateur Beacons". Radio User. 3 (5): 56–58. ISSN 1748-8117. The article includes the following definition for beacons licensed in the Amateur Radio service: "A station in the Amateur Service or Amateur Satellite Service that autonomously transmits in a fixed format, which may include repeated data or information, for the study of propagation, determination of frequency or bearing, or for other experimental purposes".
- Talbot, Andy (G4JNT) (August 2008). "Amateur Beacons". Radio User. 3 (8): 30–33. ISSN 1748-8117.
- Keeton, Kelly R. (K7MHI) (17 November 2016). "Re: Beacon Operating frequencies". Retrieved 28 February 2020.
- "IARU Region 2 Band Plan" (PDF). International Amateur Radio Union Region 2. October 14, 2016. Retrieved September 16, 2019.
- "VHF Managers Handbook" (PDF). 7. International Amateur Radio Union Region 1. January 2015. Retrieved October 27, 2015.
- 47 CFR 97.203
- "Band Plan". American Radio Relay League. Retrieved October 27, 2015.
- "IARU Region 3 Interim Band Plan" (PDF). International Amateur Radio Union Region 3. September 3, 2019. Retrieved September 16, 2019.
- "Amateur Radio UK VHF Bandplan". Great Yarmouth Radio Club. Archived from the original on 2008-05-31. Retrieved 2008-04-27.
- "International Beacon Project". Northern California DX Foundation. 2008. Archived from the original on 2007-12-27. Retrieved 2008-02-27.
- "Aurora beacon DKØWCY". Deutscher Amateur-Radio-Club e.V. (DARC). 2004. Retrieved 2008-05-03.
- Pat Hawker, G3VA (2008). "The DK0WCY/DRA5 Propagation Beacons". Technical Topics Scrapbook – All 50 years. Potters Bar, UK: Radio Society of Great Britain. p. 98. ISBN 978-1-905086-39-9.
- Mike Willis, G0MJW (April 2008). "The GB3RAL VHF Beacon cluster". RadCom. Radio Society of Great Britain. 84 (4): 65–69. ISSN 1367-1499.
- "Welcome to the Weak Signal Propagation Reporter Network". WSPRNet.
- Hansen, Bo (OZ2M) (20 April 2017). "OZ2M".
- IARU/NDXF International Beacon Project
- Dawid SQ6EMM. "Amateur Radio Beacon List". Dawid SQ6EMM. Archived from the original on 2012-03-22. Retrieved 2012-12-06.
- R.Wilkinson, G6GVI; S.Cooper, GM4AFF; B. Hansen, OZ2M. "The 70 MHz Beacon List". The Four Metres Website. Archived from the original on 2008-02-18. Retrieved 2008-04-27.
- Martin Harrison, G3USF. "Worldwide List of HF Beacons" (TEXT). Retrieved 2008-04-27.
- Martin Harrison, G3USF. "Worldwide List of 50 Beacons" (TEXT). Retrieved 2008-04-27.
- Thomas M. Rösner, DL8AAM (2005). "The DL8AAM QSL Collection: QSLs from Radio Beacons". Archived from the original on September 10, 2007. Retrieved 2008-01-05.
- John Jaminet, W3HMS and Charlie Heisler, K3VDB (2007). "Building a beacon for 2401 MHz". CQ VHF. CQ Communications, Inc. 10 (3): 44–46. ISSN 1085-0708.CS1 maint: multiple names: authors list (link)
- Andrew Talbot, G4JNT. "Design and building of the 5 MHz beacons, GB3RAL, GB3WES and GB3ORK" (PDF).
- Andy Talbot, G4JNT. "The Next Generation of Beacons for the 21st century" (ppt).
- "UK Amateur Radio & Microwave Beacons". UK Microwave Groups (UKMuG). Retrieved 2008-04-27.
- Bo Hansen, OZ2M. "The Next Generation Beacons platform".
- Bo Hansen, OZ2M. "PI4 – a digital modulation for beacon purposes".