Amateur Radio Callsign Validator

Amateur radio callsigns: how the ITU divides the spectrum into national prefixes

An amateur radio callsign is the unique identifier that every licensed radio amateur uses to sign every transmission. The framework is set globally by the International Telecommunication Union (ITU), which allocates blocks of prefixes to each country in its Radio Regulations; each national regulator (in Brazil, ANATEL; in the US, the FCC; in the UK, Ofcom) then issues individual calls from its block. The license also bestows operating privileges on specific frequency bands and modes.

A callsign typically follows the pattern prefix + region digit + suffix. The prefix encodes the country, the digit encodes the region or call area, and the suffix (1 to 3 letters) is the operator's individual identifier. Example: PY2ABC = Brazil (PY), region 2 (Sao Paulo), operator ABC. Examples from other countries include W1AW (ARRL HQ in the US), G0RDY (UK), JA1XYZ (Japan), VK2AB (Australia) and LU1ZZZ (Argentina).

Brazilian prefixes and regions

• PY: most Brazilian amateurs; the default block issued by ANATEL.
• PP: less common, often historic or special allocations.
• PT: secondary amateur block.
• PR, PS, PU, PV, PW: less common variants assigned to specific license classes or special purposes.
• PR0, PT0, PY0: used for special expeditions, contest stations and oceanic island activities (Fernando de Noronha, Trindade, Saint Peter and Saint Paul).

The region digit identifies the call area within Brazil: 1 Rio Grande do Sul / Santa Catarina, 2 Sao Paulo, 3 Rio de Janeiro / Espirito Santo, 4 Minas Gerais, 5 Parana, 6 Bahia / Sergipe / Northeast, 7 Northeast (Pernambuco, Paraiba etc.), 8 North/Amazon, 9 Centro-Oeste, 0 reserved for special or oceanic stations.

License classes in Brazil

ANATEL grants three license classes governed by Resolucao 449/2006 and successors. Class A is the highest privilege level (full HF access, all modes); Class B permits operation on portions of HF; Class C is restricted to VHF/UHF voice and digital. The Brazilian amateur community is organized around LABRE (Liga de Amadores Brasileiros de Radio Emissao), the IARU-member representative that handles QSL bureau, exam coordination and policy lobbying with ANATEL.

Bands, modes and digital activity

Amateur bands range from HF (3.5-30 MHz) used for long-distance shortwave contacts, through VHF (144 MHz) and UHF (430 MHz) for local FM and repeater work, to microwave bands at 1.2/2.4/5.7 GHz. Popular modes include SSB voice, CW (continuous-wave Morse), FM for repeaters, FT8/FT4 weak-signal digital, JS8Call, PSK31, and emergency-oriented Winlink. Each mode has a typical sub-band by gentleman's agreement under the IARU band plan.

Awards, expeditions and on-the-air programs

• DXCC (DX Century Club): work and confirm contacts with 100+ entities from the ARRL DXCC list.
• WAS (Worked All States) and WAC (Worked All Continents): regional awards.
• SOTA (Summits on the Air): activations from mountain summits.
• POTA (Parks on the Air): activations from national/state parks.
• IOTA (Islands on the Air): contacting island groups.
• WWFF (Worldwide Flora & Fauna): activations from protected areas; the Brazilian sub-program is WWFF-PY.

QSL cards and electronic logging

After a contact, amateurs traditionally exchange a paper QSL card confirming date, frequency, mode and signal report. Cards travel through the QSL bureau of each national IARU member (LABRE in Brazil) or direct mail. Today, most contacts are also confirmed electronically through Logbook of The World (LoTW) by ARRL, QRZ.com logbook, eQSL and Club Log. APRS (Automatic Packet Reporting System) transmits real-time location, weather and short messages tied to a callsign suffix such as PY2ABC-9 for a vehicle.

Special suffixes and portable identifiers

• /P portable operation (battery in the field).
• /M mobile (vehicle).
• /MM maritime mobile.
• /AM aeronautical mobile.
• /R when transmitting through a repeater identifier.
• Reciprocal operation: visiting amateurs add the host-country prefix (e.g., PY2/W1AW = US amateur W1AW operating in Sao Paulo, Brazil).

Common pitfalls

• Pirate operation: transmitting without a callsign is a crime under ANATEL Resolucao 4566 and the FCC Part 97 equivalent — never use a fake call.
• Out-of-band operation: licensed amateurs must respect the privileges of their class; transmitting outside your authorized band is grounds for licence suspension.
• Confusing callsign formats: aviation/maritime callsigns have completely different structures.
• Letter case: callsigns are case-insensitive in transmission but logs and QSL cards conventionally use uppercase.

FAQ

Is the prefix PY or PT?

Both are valid for Brazil. PY is by far the most common and is issued first; PT is a secondary block also assigned by ANATEL. Other Brazilian prefixes (PP, PR, PS, PU, PV, PW) exist for specific allocations.

Do I need a licence to operate?

Yes. In Brazil ANATEL requires an exam and registration; operating without a valid licence and callsign is a crime. In the US the FCC issues licences and free callsigns after the Technician exam.

Is a callsign valid internationally?

Yes. Under the ITU framework and reciprocal-operation agreements (such as the Inter-American Convention and CEPT Recommendation T/R 61-01), a Brazilian PY can operate in many countries by adding the host prefix, e.g., PA/PY2ABC in the Netherlands.

What is QRZ.com used for?

QRZ.com is the global online callsign database and logging platform. You can look up any callsign worldwide, see the operator's profile and QSL preferences, and upload contacts that count toward awards.

Does this validator confirm the callsign is registered with ANATEL?

No. The validator only checks the structural pattern (prefix + digit + 1-3 letter suffix) and Brazilian prefix coverage in your browser. To confirm an active licence, query the ANATEL Sistema Mosaico or QRZ.com.