IARU REGION 1 CONFERENCE 1996
29 September – 6 October
Dan Panorama, Tel-Aviv, Israel
Committee C4 Doc/96/TVI/C4.6
Input paper from Region 1 HF Beacon Coordinator to IARU HF Committee
It is proposed that: the IARU document ‘BEACON POLICY AT 28 AND 50 MHZ’ be changed to ‘BEACON OPERATION AT HF AND 50 MHZ’ 1 and that the following document be approved as a guide to good practice for IARU Region 1 HF beacon operation.
IARU REGION 1 HF BEACONS – A GUIDE TO GOOD PRACTICE2
Beacon transmissions have long been used as guides to the presence of HF openings and have contributed signiﬁcantly to our knowledge of propagation. However, the number of HF beacons is steadily increasing and the amount of spectrum available is under pressure. It is more important than ever that beacon operators are aware of the technical parameters required, the reasons for them and the procedure to be followed to obtain an agreed frequency. This is particularly important in respect of bands with narrow beacon allocations.
It is not the intention of this document to prescribe the exact purpose of any beacon, its power level or the number of beacons in any country. It is also not intended to be applied rigorously to experimental or special-purpose beacons. It should, however, apply to the vast majority of HF beacons for propagation monitoring.
1. COORDINATION PROCEDURE
The beacon proposal should be agreed within the national society (with consultation with neighbouring societies where appropriate) and a provisional frequency chosen. The proposed frequency should be submitted to the IARU regional HF beacon coordinator to check for potential interference problems.
2. TRANSMISSION MODE
ln the interests of spectrum economy the preferred transmission mode at HF is A1a CW. If F1a is used the shift should not exceed 250 Hz, with MARK on the nominal frequency and SPACE on the lower. Care must be taken to ensure that the transmission has the lowest possible levels of spurious signals, key clicks and phase noise.
3. FREQUENCY ACCURACY AND SPACING
All beacons should operate within the IARU-designated sub-bands. Additionally, solo beacons should avoid frequencies assigned by the IARU to frequency-sharing networks. Frequencies are currently assigned either on an exact kHz (e.g. 28 205.0) or a half kHz (e.g. 28 205.5). (However, if beacon numbers continue to grow 100 Hz spacing may be introduced.) Beacons should normally be capable of operating within +/- 25 Hz of their nominal frequency.
As beacons are often heard at very low signal levels, often among spurious signals, it is important that their message be simple, unambiguous and repeated frequently. It is also necessary to have a short period of carrier for frequency checking and strength measurement purposes, and to make it easy to distinguish the mark frequency where FSK is used.
The message should therefore consist of 5 – 10 seconds of carrier followed by the call sign and (if required) the grid locator at 10 – 12 words per minute. Nothing more. No gaps in transmission.
To avoid inefﬁcient use of spectrum and presenting an unduly pessimistic impression of propagation conditions a minimum [maximum] power of 10 watts e.r.p. is recommended at HF. Other than this there are no recommendations as to power or antennas other than suitability for purpose and the need to minimise interference.
Operation should be 24-hour continuous. (This does not preclude beacons that switch to different frequencies or beam headings on a regular basis.)
Beacon operators must try to ensure that the operational parameters of their beacons remain as stable as possible and that non-operational time is kept to a minimum.
It is important that the operational parameters and status of all beacons be widely known. This information should be sent to the Region 1 HF beacon coordinator via the local beacon coordinator or spectrum manager at least once a year or whenever the operational parameters are changed.
Martin Harrison, G3USF
Region 1 HF Beacon Coordinator
Beacons on Bands Below 14 MHz
The amateur beacon service has for many years provided a valuable role in offering amateurs and short wave listeners indicators of the availability of particular paths and a base for propagation studies. In recognition of this certain frequencies are reserved for beacons in the IARU band plan for the bands between 14 and 28 MHz.
No such allocations are made for bands below 14 MHz, with the exception of 7 MHz in sub-equatorial Africa, where special circumstances apply. However, the general view of national societies in IARU Region 1 is that beacons in continuous unattended operation on bands between 1,8 and 10 MHz are unnecessary and, even where they run low power, they can be a cause of harmful interference to normal operating and of annoyance to operators on these bands.
In recent years a number of beacons have started operation on these bands. They have no clearly defined purpose and are not part of any coordinated programme of development. The bands concerned are fully occupied and their propagation characteristics are already very well established and fairly predictable.
This matter was discussed at the 2005 conference of IARU (Region 1), which adopted a motion from the Danish national society, EDR, that beacon operation on 7 and 10 MHz was ‘discouraged’. This is now the official policy of IARU Region 1. Member societies are requested to use their best efforts to ensure it prevails. Individuals are strongly urged to refrain from reporting the signals of unauthorised beacons or spotting them on the web cluster.
The exception to this general rule is for beacons used in connection with a propagation research project endorsed by the relevant national society and the HF beacon coordinator and subject to review by the subsequent triennial regional conference. Normally any such project would be for a limited period.
The conference agreed an exception to the general rule, in the case of DK0WCY’s transmissions on 3,5 and 10 MHz. There is a possibility of extending the DK0WCY service by time-sharing its frequencies to provide (say) near-real-time MUF data from other locations. Anyone wishing to explore the possibility of such a development should contact the DARC HF manager (and DK0WCY team leader), Ulrich DK4VW.
While the decision of the conference did not specifically refer to 1.8 and 3.5 MHz, my personal understanding is that beacon operation should also be discouraged on those bands. An earlier Region 1 resolution stated that long- running beacons should not be established on 137 kHz.
If you are interested in designing or operating beacons, there are other possibilities on other bands. In particular:
(1) The construction of beacons for countries which are not currently covered and where local operators are not in a position to build a beacon.
(2) Beacons that share a frequency (similar to the existing IBP/NCDXF network), thus economising spectrum.
(3) Designing and constructing more technically advanced beacons to replace an earlier generation of beacons. We should always recognize that there are already many beacons and our frequencies are limited. Accordingly, we have always to ask ourselves, before beginning a new project, what is its purpose and what will it add to our hobby.
It is recommended that HF Beacons may be established on the 1,8, 3,5 and 7 MHz band in the regions of Africa south of the Equator. (REC/99/LH/C4.1 – Lillehammer 1999)
Contact the Region 1 HF Beacon Coordinator on e-mail firstname.lastname@example.org