Dec 11, 20233 min read

How to Receive Live Satellite Images Using Simple Equipment

Sometimes I figure something out by accident this is one of those times...

Weather satellites orbiting the Earth provide a fascinating and practical way to observe weather patterns from space. Recently, there has been growing interest in capturing live images from these satellites. Here, we present a beginner-friendly guide to receiving images from weather satellites like NOAA 15, 18, and 19 using minimal equipment.

Understanding Satellite Types and Orbits

Before delving into the how-to, it's essential to understand a bit about the satellites themselves:

Low Earth Orbit Satellites: These orbit approximately 500-1000 miles above the Earth's surface and complete an orbit roughly every 90 minutes. The best time to view these with the naked eye is early morning or late evening.
Polar Orbiting Satellites: They cross over each pole every day and are used for weather monitoring. Notably, NOAA satellites follow this type of orbit.
Geostationary Orbits: These satellites maintain a fixed position relative to the Earth's surface and are typically used for telecommunications and some weather applications.

Equipment You'll Need

Basic Radio Scanner or Handheld Transceiver: A device capable of receiving VHF FM signals, specifically in the 137 MHz band, is essential. Popular and budget-friendly options include Baofeng radios.
Software-Defined Radio (SDR): A more advanced option, the RTL-SDR dongle, is a versatile tool for receiving a wide range of signals, including those from weather satellites.
Antenna: While the basic antenna that comes with the radio or SDR can work, specialized antennas like V-dipoles or QFH antennas offer better reception.
Computing Device: A smartphone or a computer is required to process the signals into images.

Steps for Receiving Satellite Images

Using a Handheld Radio

Tune to the Right Frequency: Each NOAA satellite transmits on a slightly different frequency in the 137 MHz band.
Recording the Signal: Use a smartphone with a sound recording app to capture the audio output of the radio during a satellite pass.
Decoding the Signal: Transfer the recorded audio to a computer and use decoding software like WXtoImg or a web-based service to convert it into an image.

Using Software-Defined Radio (SDR)

Setup: Connect the RTL-SDR dongle to a computer and set up the antenna in an open space.
Tuning and Recording: Use software like SDRSharp or SDR++ to tune to the satellite's frequency and record the pass.
Decoding: Process the recorded signal using software like NOAA APT or SatDump to extract the image.

Tips for Better Reception

Optimal Antenna Positioning: The antenna should ideally be positioned outside, away from obstructions. For polar orbiting satellites, orienting the antenna correctly relative to the satellite's path is crucial.
Understanding Pass Times: Use websites like n2yo.com to track the satellite's path and schedule your listening session accordingly.
Patience and Practice: It may take several attempts to get a clear image. Experiment with different settings and times to find what works best for you.

Enhancing Your Setup

Advanced Antennas: Building or purchasing a QFH antenna can significantly improve signal reception.
Filters and Amplifiers: Devices like the Sawbird NOAA filter can boost signal strength and reduce interference.
Automation: For enthusiasts, setting up an automated system with a Raspberry Pi and appropriate software can streamline the process of capturing and processing images.

Final Thoughts

Capturing images from weather satellites is an exciting and educational hobby that combines elements of radio technology, space science, and weather observation. With some basic equipment and patience, anyone can start receiving stunning images from space, providing a unique perspective on the Earth's weather systems.