Brazilian amateur radio operator

André Couto
PU2DIY

PU2DIY is André Couto’s amateur radio callsign. This page brings together interests and activities related to radio experimentation, antennas, APRS, amateur radio satellites, TinyGS and emergency communications.

View QRZ page View TinyGS station

What is amateur radio?

Amateur radio is a technical, scientific, educational and operational activity focused on radio communication. Amateur radio operators study propagation, electronics, antennas, modulation, digital protocols and responsible use of the radio spectrum.

Beyond station-to-station contacts, amateur radio encourages building and adjusting equipment, experimenting with new technologies and gaining practical knowledge in telecommunications.

Real contributions

Historically, amateur radio operators have helped popularize long-distance communication techniques, digital networks, amateur satellite communication and volunteer support during emergencies. Projects such as AMSAT and ARISS also bring students closer to space science and radio engineering.

Amateur radio is not just “talking on the radio”: it is technical learning, experimentation and community service.

Antennas and experimentation

📡

Building

Simple antennas such as dipoles, verticals, J-poles and yagis help explain gain, polarization, impedance, SWR and impedance matching.

📈

Measurement

Tools such as SWR meters, NanoVNAs and SDR receivers help test performance, tune resonance and compare practical results.

🌎

Propagation

Each band behaves differently. VHF/UHF favor line-of-sight and satellites; HF enables long-distance contacts through ionospheric reflection.

🛰️

APRS

APRS, the Automatic Packet Reporting System, is a digital system widely used by amateur radio operators to transmit position, telemetry, short messages, map objects and operational information. It can work over radio, the internet or in hybrid form through gateways.

Why is it useful?

With APRS, it is possible to track mobile stations, balloons, repeaters, events, expeditions, weather conditions and field activity. In emergencies, it can help visualize teams, resources and support points.

Amateur radio satellites

Amateur radio satellites enable contacts and experiments on VHF, UHF and other bands, often using relatively simple equipment. Many are CubeSats or small educational satellites carrying repeaters, transponders, telemetry beacons or experimental payloads.

Operation
The operator follows the satellite pass, points the antenna, compensates for Doppler shift and transmits or receives at the right moment.
Education
Amateur space projects bring students closer to electronics, orbital mechanics, embedded programming, radio and citizen science.
Reception
Even without transmitting, it is possible to receive beacons, telemetry and satellite signals using SDRs, simple antennas and decoding software.

SAT DOPPLER

SAT DOPPLER — Satellite Tracking with Doppler Correction is an amateur satellite tracking module for the Quansheng UV-K5 radio, with automatic real-time frequency correction for the Doppler effect.

The project is directly connected to André Couto’s, callsign PU2DIY, interest in amateur radio satellites, VHF/UHF experimentation, antennas, firmware and hands-on operation during orbital passes.

View SAT DOPPLER on GitHub

Features

  • Automatic Doppler correction for RX and TX during satellite passes.
  • Manual frequency adjustment in 1 kHz steps.
  • FM, USB (SSB) and AM support, respecting the modulation configured in the channel.
  • Monitor mode, with squelch override, using SIDE1.
  • Transmission with CTCSS and power configured in the channel.
  • No hardware modification or expanded EEPROM required.

TinyGS

TinyGS is a global collaborative network of small ground stations mainly focused on receiving satellite telemetry, especially from CubeSats and other small satellites. Many stations use low-cost boards with LoRa radios to receive packets and share data with the community.

André Couto, callsign PU2DIY, participates in the TinyGS ecosystem with a station registered on the platform.

TinyGS station linked to PU2DIY

The page below shows the TinyGS station, including activity, receptions and public information available on the platform.

Open PU2DIY station on TinyGS

Amateur radio in emergencies

When conventional networks fail or become congested, amateur radio operators can support local and regional communications on a voluntary, organized basis, complementing official agencies. The value lies in technical independence: independent power, improvised antennas, portable operation and practical knowledge of propagation.

🔋

Autonomy

Stations can operate with batteries, solar power, temporary antennas and portable equipment.

🗺️

Coordination

Voice and data networks can support message exchange, location sharing and operational reports.

🤝

Service

Operation should be responsible, voluntary and aligned with real community needs.