GAREC 2009

Centre of Activity FrequenciesExperiences and the future

Greg Mossop, G0DUB

Centre of Activity Frequencies

The concept of 'Centre of Activity' Frequencies was proposed at GAREC 2005 but no frequencies were specified

Proposal adopted by the IARU Region 1 conference in the same year.

There was some logic in the choice of frequencies...

Centre of Activity Frequencies

CoA are the same in all 3 regions for 15, 17 and 20m. Only these bands provide reliable intercontinental coverage and the bands are reasonably harmonised across all 3 regions.

20m 14.300 MHz 17m 18.160 MHz 15m 21.360 MHz

14.300 chosen because it “is the primary intercontinental channel in use by the US for its Katrina response operation.”

Centre of Activity Frequencies

CoA at 80m and 40m are set on a region by region basis

“The logic for this is that harmonisation of CoAs at 40 and 80m would be difficult, and generally propagation would not support intercontinental traffic.”

This process was repeated in the other two IARU regions...

Centre of Activity Frequencies

Region 1 Region 2 Region 33760 3750 or 3985 37607110 7060, 7240 or 7290 706014300 14300 1430018160 18160 1816021360 21360 21360

7060kHz may still be used in Region 1 by countries which do not have access to 7.1-7.1MHz

Centre of Activity Frequencies

We do have some problems with the use of the frequencies...

Recognition by other Radio Amateurs. Adoption by local Emergency

Communications Groups Clashes with existing users of frequencies. How to we manage a 'centre of activity' with

multi-modes in use ?

Centre of Activity Frequencies

Centre of Activity Frequencies

Centre of Activity Frequencies

Centre of Activity Frequencies

Some of the frequencies chosen have existing users, not all emergency communications related.

Proposal to move 80m CoA frequency from 3760kHz to 3750kHz at IARU Region 1 conference failed though this would have solved some problems in the UK.

Centre of Activity Frequencies

Some changes such as moving from 7.060 to 7,110 MHz in Region 1 should have been good. Away from contest segment of band. No existing amateur usage.

But remaining broadcast usage has stopped groups moving to the new frequency in some areas.

Centre of Activity Frequencies

We still have questions to answer about how to operate on the CoA frequencies.

How do we avoid inter-regional QRM ?

How do we identify a control station on the frequency ?

How do we separate different modes on the frequency ?

Centre of Activity Frequencies

As Solar activity increases, inter-regional QRM will become more frequent – it is already happening now.

In GlobalSET where we have identified Control Stations by callsigns, they are still affected by QRM.

As conditions change, changing mode can be as effective as changing band.

Centre of Activity Frequencies

We need to remember that these are;

Centres of Activity – not spot frequencies !

Encourage spreading out from the centre. Improve co-ordination between regions. Maybe develop a protocol that Data is LF

and voice HF of centre as conditions change.

Centre of Activity Frequencies

The solutions are in our hands through the GAREC conferences.

This is the time to get things organised, not when an emergency has happened.

Where do we go next ?

Any Questions ?

Websitewww.iaru-r1.org

Emailgregm@raynet-hf.net