For many people, space is a distant and mysterious realm — something to observe through telescopes or follow in the news. But few realize that it’s entirely possible to listen in on space signals from your own home using affordable equipment and some curiosity. Satellite communication is no longer just for professionals: with a small investment, a simple antenna, and the right software, you can start receiving real satellite signals from orbit.
In this article, we’ll explore how to get started with amateur satellite listening, what hardware and software are needed, how to decode transmissions, which satellites to monitor, and what exciting data you can receive — from weather images to SSTV pictures from the ISS. Whether you’re a beginner or a tech hobbyist, this guide will get you ready to explore the radio side of space.
1. What is satellite communication?
Satellite communication involves transmitting information (audio, data, images, etc.) from a ground station to a satellite in orbit, which either retransmits or relays the signal back to Earth. Most signals are transmitted via radio frequency (RF) waves across specific bands (VHF, UHF, S-band, etc.).
2. A brief historical overview
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1957 – The launch of Sputnik-1, the first satellite, which transmitted simple radio beeps received worldwide by radio hobbyists.
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1960s – The emergence of early weather and military satellites.
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1970s – Introduction of OSCAR satellites — amateur radio satellites.
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2000s – Growth of software-defined radio (SDR) made satellite listening affordable.
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2020s – Global hobbyist communities, powerful free software, and low-cost receivers made satellite monitoring popular and accessible.
3. Which satellites can you listen to as a hobbyist?
3.1 Low Earth Orbit (LEO) satellites
These satellites fly at altitudes between 500–1500 km and are the most accessible for hobbyists.
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NOAA satellites – US weather satellites that transmit APT-format images.
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METEOR-M series – Russian weather satellites transmitting high-resolution LRPT images.
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ISS (International Space Station) – Occasionally transmits SSTV images during amateur events.
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Amateur radio satellites (e.g., AO-91, AO-95) – Transmit voice, telemetry, and digital data.
3.2 Higher orbit satellites
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Geostationary satellites (e.g., QO-100, Inmarsat) – Require precise pointing and more advanced setups.
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Starlink, OneWeb – Not directly listenable, but their signals can be observed as part of the spectrum.
4. What you need: hardware and software
4.1 Hardware
| Device | Description |
|---|---|
| SDR receiver (e.g., RTL-SDR v3) | USB radio tuner, around $20 |
| Antenna | Dipole, QFH, turnstile, or Yagi, depending on satellite |
| Coaxial cable | Low-loss, like RG-6 or RG-213 |
| Computer | Windows, Linux, or macOS |
4.2 Software
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SDR# (SDRSharp) – Popular SDR app for Windows
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GQRX – SDR tool for Linux/macOS
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Orbitron / GPredict – Satellite tracking software
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WXtoImg / SatDump – For decoding NOAA/METEOR weather images
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QSSTV / MMSSTV – For decoding SSTV images from ISS
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Direwolf / FLDigi – For decoding amateur digital modes (e.g. APRS)
5. Getting started: step-by-step guide
Step 1 – Choose your target satellite
Use satellite tracking tools like https://www.n2yo.com or GPredict to find when a satellite will pass over your location.
Step 2 – Plug in your SDR receiver
Insert your RTL-SDR dongle into a USB port, install drivers (e.g. Zadig for Windows), and ensure the system recognizes it as an SDR device.
Step 3 – Set up your antenna
Position it outdoors or near a window with a clear view of the sky. For LEO satellites, use circularly polarized antennas like QFH or turnstile for best results.
Step 4 – Tune in and decode
Start your SDR software, tune to the correct frequency (e.g. NOAA 137.100 MHz), and watch your audio signal transform into images or data with decoding tools.
6. Practical examples
6.1 Receiving NOAA weather images (APT)
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Frequency: 137.100–137.9125 MHz
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Modulation: Analog FM + APT signal
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Software: SDR#, WXtoImg
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Output: Black-and-white satellite images showing cloud cover and weather fronts
6.2 Receiving METEOR-M images (LRPT)
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Frequency: ~137.900 MHz
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Modulation: Digital QPSK
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Software: SatDump
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Output: High-resolution, full-color weather images
6.3 Receiving SSTV from the ISS
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Frequency: 145.800 MHz
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Occasional events (e.g. ARISS SSTV)
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Software: MMSSTV
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Output: Color images sent by astronauts or automatic systems, slow-scan television
7. Tips for beginners
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? Start with NOAA – Their strong signals and consistent schedules make them beginner-friendly.
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? Track satellite passes carefully – You usually have only a few minutes to catch a signal.
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? Be patient – First results may take time.
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? Join communities – Reddit (r/RTLSDR), Discord groups, RTL-SDR.com blog, Facebook groups.
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? Build your own antennas – A simple DIY dipole can already give great results.
8. Legal considerations: what is allowed?
In most European countries (including Hungary), it’s legal to receive unencrypted transmissions as long as:
✅ They are not encrypted
✅ They are not explicitly forbidden by law
✅ You don’t rebroadcast or misuse them
⚠️ Transmitting on amateur frequencies requires a radio license (e.g., from NMHH). Listening to NOAA, METEOR, ISS SSTV, and amateur satellites is fully legal.
9. Future trends
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CubeSat boom – More universities and organizations are launching small satellites with open telemetry.
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Web-based SDR stations – Listen to satellites via the web (e.g. https://satnogs.org)
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AI-powered decoders – Noise reduction, image enhancement, and auto-decoding with machine learning
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QO-100 popularity – A geostationary ham radio satellite offering real-time transponder access from Africa to Southeast Asia
Conclusion
Hobby satellite reception is easier than ever in 2025. You don’t need expensive gear — just a cheap SDR dongle, a simple antenna, and some time and curiosity. The thrill of receiving a live weather image from orbit or a signal from the ISS is priceless — and completely achievable.
This hobby is not just fun, it’s educational: you’ll learn about radio waves, satellite orbits, atmospheric effects, and signal processing. Whether you’re a student, tinkerer, or lifelong learner, satellite listening opens a door to the space age from the comfort of your home.
