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Sending your first message

Send a custom test message over the Astrocast satellite network that will display in the Astrocast Portal.

Check next satellite pass

Check the next Astrocast satellite pass at your location in the Astrocast Portal.

Hardware Setup


15 minutes before a satellite pass, install your setup outside with a clear view to the sky, free from trees, buildings, flying cars and elephants, etc.



Connect the Astronode Satellite Board to your computer with either the UART Cable 1.8m or the RS232 Cable 5m, see Interfaces.


The setup below uses the default casing with the Astronode Satellite Board inside and the UART interface to connect the computer.


  • Make sure to put some distance between your computer and the DevKit, as this could lead to interferences.
  • Using another type of housing than the one provided with the DevKit might impact the performance of the RF communication.

Use the Astronode GUI

The Astronode Graphical User Interface (GUI) is a Windows application helping you configure the Astronode DevKit. The GUI also allows you to send data and monitor events such as acknowledgement reception on the Astronode S. It is compatible with Wi-Fi and Satellite board.

Download & Installation

See Tools & Libraries section for the GUI installer.

  • Requires Microsoft Windows 10 or above.
  • Requires .NET 5.0 Runtime
  • If the DevKit is not recognized properly when you plug it, you might need to install a FTDI driver.


Launch the Astronode GUI application on your computer.

Select COM Port

Connecting the Astronode DevKit to your computer through a TTL cable should mount a COM Port on your computer. You need to select the right port.

Here is the process on Microsoft Windows 10:

  1. Open Device Manager.
  2. Click on View in the menu bar and select Show hidden devices.
  3. Locate Ports (COM & LPT) in the list.
  4. Check for the COM ports by expanding the list.

Set geolocation (optional)

  1. Enter the Latitude.
  2. Enter the Longitude.
  3. Set Add to messages to ON.
  4. Click on Set geolocation config.

Setup Wi-Fi network (only for Wi-Fi board)


Only 2.4 GHz Wi-Fi access points are supported.

  1. Enter the SSID of your Wi-Fi network.
  2. Enter the Password for your Wi-Fi network.
  3. Enter the Astrocast Token with Wi-Fi DevKit role (Learn how to Create an access token).
  4. Click on Set Wi-Fi config.

Enqueue a message

  1. Enter your message into Enter your message textbox. A message can be up to 160 bytes.
  2. Click on 📨 Queue message.

For a first trial, we recommand you to keep your payload short (like 10-30 bytes).

Get an ACK from the satellite

If the transmission is succesful, your DevKit will get an acknowledgement (ACK) from the satellite.

You will see the "Acked" circle on the Astronode GUI turn to green. 🟢



Delete the oldest message in the queue

Click on Wipe last message in buffer.

Retrieve your message in the Astrocast Portal

  1. Wait up to 24 hours* (current maximum latency).
  2. Go to the Astrocast Portal.
  3. Click on Messages in the sidebar.
  4. See your message in the list.