Radio propagation beacon

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QSL card from DRA5 radio propagation beacon
QSL card from DRA5 radio propagation beacon

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, VHF, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test antennas and receivers.[1]

Contents

[edit] Transmission characteristics

Most beacons operate in CW (A1A) and transmit their identification (callsign and location). Some of them send long dashes to facilitate signal stength measurement. A small number of beacons transmit morse code by frequnecy modulation (F1A). A few beacons transmit signals in digital modulation modes, like RTTY (F1B) and PSK31 (G1B).

[edit] 160 meters beacons

The IARU R2 bandplan reserves the range 1999-2000 kHz for propagation beacons.

[edit] 10 meters beacons

Most HF radio propagation beacons are found in the 10 meters (28 MHz) frequency band, where they are good indicators of Sporadic E-layer ionospheric propagation.

According to IARU bandplans, the following 28 MHz frequencies are allocated to radio propagation beacons:

IARU Region Beacon allocations
R1
  • 28190-28199 Regional Time Shared
  • 28199-28201 WW Time Shared
  • 28201-28225 Continuous Duty
R2[2]
  • 28190-28199 Regional Time Shared
  • 28199-28201 IBP/NCDXF
  • 28201-28225 Beacons, continuous duty
  • 28225-28300 Shared
R3
  • 28190-28200 IBP

[edit] 6 meters beacons

In the 6 meters (50 MHz) band, beacons operate in the lower part of the band, in the range 50000-50080 kHz. The ARRL bandplan recommends 50060-50080 kHz for beacons in the USA. Due to unpredictable and intermittent long distance (DX) propagation, usually achieved by a combination of F2 and Es ionospheric reflections, beacons are very important in providing early warning for 50 MHz openings.

[edit] VHF/UHF beacons

Beacons on 144 MHz and above 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 in higher badns vary widely in differet IARU regions and countries. The current UK allocation, which also reflects IARU R1 recommendations is the following: [3]

Band 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

[edit] Beacon projects

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 ITU and the IARU.

[edit] IARU Beacon Project

The International Beacon Project (IBP), which is coordinated by the Northern California DX Foundation and the International Amateur Radio Union (IARU), consists of 18 HF propagation beacons worldwide, which transmit in turns on 14100 kHz, 18110 kHz, 21150 kHz, 24930 kHz, and 28200 kHz.[4]

[edit] 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, JO29po) and at Darwin, Australia (callsign VL8IPS, PH57pj). The beacons operated on frequencies 5471.5 kHz, 7871.5 kHz, 10408.5 kHz, 14396.5 kHz, and 20948.5 kHz. [5]. Since 2002, there have been no reception reports for these beacons and the relevant ITU web pages have been removed.[6]

[edit] DARC beacon project

The German Amateur Radio Club (DARC) sponsors two beacons which transmit from Scheggerott, near Kiel ( JO44vq).[7] 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 CW (Morse code for aural reception), RTTY and PSK31.[8][9]

[edit] 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 ( IO91in), GB3WES in Cumbria ( IO84qn) and GB3ORK in the Orkney Islands ( IO89ja). 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). [10]

[edit] Notes and References

  1. ^ 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.
  2. ^ New IARU Region 2 bandplan introduced in January 2008
  3. ^ Amateur Radio UK VHF Bandplan. Great Yarmouth Radio Club. Retrieved on 2008-04-27.
  4. ^ International Beacon Project. Northern California DX Foundation (2008). Retrieved on 2008-02-27.
  5. ^ HF 0-20 MHz. Retrieved on 2008-03-14.
  6. ^ Resolution ITU-R 27: HF Field-strength measurement campaign (PDF) (1993). Retrieved on 2008-03-12.
  7. ^ Aurora beacon DKØWCY. Deutscher Amateur-Radio-Club e.V.(DARC) (2004). Retrieved on 2008-05-03.
  8. ^ DK0WCY operates also a limited service beacon on 3579 kHz at 0720-0900 and 1600-1900 local time
  9. ^ Pat Hawker, G3VA (2008). "The DK0WCY/DRA5 Propagation Beacons", Technical Topics Scrapbook - All 50 years. Radio Society of Great Britain, 98. ISBN 9781-9050-8639-9. 
  10. ^ Mike Willis, G0MJW (April 2008). "The GB3RAL VHF Beacon cluster". RadCom 84 (04): 65-69. Radio Society of Great Britain. 

[edit] See also

[edit] Further reading

  • John Jaminet, W3HMS and Charlie Heisler, K3VDB (2007). "Bulding a beacon for 2401 MHz". CQ VHF 10 (3): 44-46. CQ Communications, Inc. ISSN 1085-0708.