WARC Bands: Origin, History and the Gentlemen’s Code

In amateur radio, not all HF bands are equal. Some are wide, crowded, and heavily used during contests. Others are narrow, quieter, and operate under a different culture of restraint. The WARC bands belong to the second category.

The WARC bands are three HF amateur allocations created after the 1979 World Administrative Radio Conference:

• 30 metres – 10.100 to 10.150 MHz
• 17 metres – 18.068 to 18.168 MHz
• 12 metres – 24.890 to 24.990 MHz

They are narrow bands: 30 metres is only 50 kHz wide, while 17 metres and 12 metres are each 100 kHz wide. Because of that narrowness, and because 30 metres is a secondary amateur allocation, these bands have developed a strong operating culture based on careful use, low interference, and no contest activity.

Allocation Status

The three WARC bands do not all have the same regulatory status.

30 metres, 10.100 to 10.150 MHz, is allocated to the amateur service on a secondary basis. Amateur stations must not cause harmful interference to primary users and must accept interference from them.

17 metres, 18.068 to 18.168 MHz, is a primary amateur allocation.

12 metres, 24.890 to 24.990 MHz, is a primary amateur allocation in ITU Region 3.

Malaysia is in ITU Region 3, so Malaysian amateurs should read these bands together with national licensing conditions and the IARU Region 3 band plan. Where national regulations and the regional band plan differ, national regulations prevail.

IARU Region 3 Band Plan Source

This article is corrected against IARU Region 3 Document R3-004, revised 3 September 2019, titled IARU Region 3 Interim Band Plan. The document states that this version was adopted at the IARU Region 3 Directors’ meeting held in Tokyo on 3 September 2019.

The 2019 document uses a newer format with columns for:

• Frequency segment
• Maximum bandwidth
• Preferred mode and generic usage
• ITU Region 3 status

Important definitions in the document include:

• Narrowband modes: CW, RTTY, PSK, JT65, WSPR, FT8, SIM31, or similar modes not exceeding 500 Hz.
• Digimodes: digital data modes restricted to the bandwidth of the frequency segment.
• Phone: SSB, DSB AM, FM, and digital voice modes with similar bandwidth not exceeding 6 kHz below 50 MHz.
• CoA: Centre of Activity frequency recommended by IARU.

30 Metres: 10.100 to 10.150 MHz

The amateur allocation is 10.100 to 10.150 MHz, but the 2019 IARU Region 3 band plan table gives preferred usage from 10.110 to 10.150 MHz:

Segment	Maximum bandwidth	Preferred usage	Status
10.110-10.130 MHz	200 Hz	CW, including 10.116 MHz QRP CoA	Secondary amateur
10.130-10.150 MHz	500 Hz	CW and narrowband digimodes	Secondary amateur

The footnotes identify common digital frequencies:

• WSPR: 10.1386 MHz
• JT65: 10.1380 MHz
• FT8: 10.1360 MHz

The 2019 Region 3 band plan also notes that some administrations allow phone in 10.115-10.140 MHz. This is not a general permission for all Region 3 amateurs. For Malaysian operators, do not treat 30 metres as a normal voice band unless Malaysian regulations specifically permit it.

The practical rule remains simple: 30 metres is a narrow, secondary band best used for CW and narrowband digital modes.

17 Metres: 18.068 to 18.168 MHz

The 2019 IARU Region 3 band plan divides 17 metres as follows:

Segment	Maximum bandwidth	Preferred usage	Status
18.068-18.095 MHz	200 Hz	CW, including 18.086 MHz QRP CoA	Primary amateur and amateur-satellite
18.095-18.110 MHz	2700 Hz	CW and narrowband digimodes	Primary amateur and amateur-satellite
18.110-18.120 MHz	2700 Hz	CW, narrowband, phone, and 18.110 MHz international beacon with 500 Hz guard band	Primary amateur and amateur-satellite
18.120-18.168 MHz	2700 Hz	CW and phone	Primary amateur and amateur-satellite

The footnotes identify common digital frequencies:

• WSPR: 18.1046 MHz
• JT65: 18.1020 MHz
• FT8: 18.1000 MHz

The band plan also identifies:

• 18.130 MHz – SSB QRP Centre of Activity
• 18.160 MHz – Digital Voice Centre of Activity
• 18.160 MHz – Emergency Centre of Activity, all modes within +/- 5 kHz

This means 17 metres is not simply “CW, digital, then phone.” The 18.110-18.120 MHz segment is shared in the plan for CW, narrowband, and phone, while the main CW/phone segment continues from 18.120 to 18.168 MHz.

12 Metres: 24.890 to 24.990 MHz

The 2019 IARU Region 3 band plan divides 12 metres as follows:

Segment	Maximum bandwidth	Preferred usage	Status
24.890-24.915 MHz	200 Hz	CW, including 24.906 MHz QRP CoA	Primary amateur and amateur-satellite
24.915-24.930 MHz	500 Hz	CW and narrowband modes	Primary amateur and amateur-satellite
24.930-24.940 MHz	2700 Hz	CW, narrowband modes, DX, phone, and 24.930 MHz international beacon with 500 Hz guard band	Primary amateur and amateur-satellite
24.940-24.990 MHz	2700 Hz	CW and phone	Primary amateur and amateur-satellite

The footnotes identify common digital frequencies:

• WSPR: 24.9246 MHz
• JT65: 24.9170 MHz
• FT8: 24.9150 MHz

The plan also identifies:

• 24.950 MHz – SSB QRP Centre of Activity
• 24.960 MHz – Digital Centre of Activity

So for Region 3, the main phone portion of 12 metres begins at 24.940 MHz, while 24.930-24.940 MHz is a mixed-use segment that includes the international beacon and guard band.

Summary of the Region 3 WARC Band Plan

Band	Allocation	Region 3 preferred segments	Key notes
30m	10.100-10.150 MHz	10.110-10.130 CW; 10.130-10.150 CW/narrowband digimodes	Secondary amateur; FT8 10.136 MHz; some administrations allow phone in 10.115-10.140 MHz
17m	18.068-18.168 MHz	18.068-18.095 CW; 18.095-18.110 CW/digimodes; 18.110-18.120 mixed including beacon; 18.120-18.168 CW/phone	Emergency CoA 18.160 MHz +/- 5 kHz
12m	24.890-24.990 MHz	24.890-24.915 CW; 24.915-24.930 CW/narrowband; 24.930-24.940 mixed including beacon; 24.940-24.990 CW/phone	SSB QRP CoA 24.950 MHz; Digital CoA 24.960 MHz

Contest Activity

The 2019 IARU Region 3 band plan does not describe WARC bands using the old informal phrase “gentlemen’s agreement.” Instead, it states the operating expectation directly:

Contest activity below 30 MHz should be restricted to the 160 m, 80 m, 40 m, 20 m, 15 m, and 10 m bands.

By omission, this keeps contest activity away from 30 m, 17 m, and 12 m. The same section encourages non-contesting amateurs to use contest-free bands during large international contests.

This is why the WARC bands remain valuable: during major contests, they provide space for ordinary QSOs, DX contacts, propagation checks, emergency readiness, and quieter operating.

Emergency Communications

The 2019 Region 3 document says amateur radio emergency communications should have priority over all other usage, especially on specified Emergency Centre of Activity frequencies during emergency communications.

For the WARC bands, the key emergency frequency in the uploaded Region 3 plan is:

• 18.160 MHz – 17 metre Emergency Centre of Activity, all modes within +/- 5 kHz

This frequency is not a private or permanently reserved channel. It is a centre of activity: a recommended gathering point during emergency operations or emergency communications training.

Good Operating Practice on the WARC Bands

Because these bands are narrow, operators should use them with more discipline than wider HF bands.

On 30 metres, use CW and narrowband digital modes unless your national administration specifically permits another mode. Keep in mind that 30 metres is secondary and narrow.

On 17 metres, protect the international beacon area around 18.110 MHz and be aware of the 18.160 MHz emergency and digital voice centre of activity.

On 12 metres, protect the international beacon area around 24.930 MHz and note that the main phone segment begins at 24.940 MHz in the Region 3 plan.

On all three WARC bands:

• Avoid contest-style operation.
• Keep transmissions narrow and clean.
• Listen before calling.
• Respect beacons and centres of activity.
• Move away from ongoing QSOs.
• Give priority to emergency communications.

Final Note for Malaysian Operators

The IARU Region 3 band plan is a regional operating guide, not a replacement for Malaysian law or licence conditions. Malaysian operators should always follow MCMC requirements first. The Region 3 band plan is best used as a practical operating reference where national rules do not give more specific instructions.

Source: IARU Region 3 Document R3-004, IARU Region 3 Interim Band Plan, revised 3 September 2019.