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Sending your first message

Get ready to send your first uplink message to space 🚀

Set up the Astronode DevKit to communicate with our satellite network in less than 20 minutes.

1. Setup your account

Register on the Portal

You need to create your account on the Astrocast Portal in order to access the data sent via the DevKit:

  1. Go to the Astrocast Portal.
  2. Click on Sign up now.
  3. Enter your Email Address.
  4. Click on Send verification code and check your email inbox.
  5. Enter the verification code and your Password.
  6. Click on Create.
  7. Multi-factor authentication: enter your Phone number and click on Send code or Call Me.
  8. Enter the code you received by SMS or phone call.

Find your DevKit

  1. Go to the Astrocast Portal.
  2. Click on Devices in the sidebar.
  3. You should find 2 devices: one for the Satellite board and one for the Wi-Fi board.

If you don't find any device in the Portal, please contact support using

2. Check next satellite pass

  1. Go to the Astrocast Portal.
  2. Scroll down to the Satellite Passes section.
  3. Optionally, you can adjust the timeframe and click on 📍.

By default, you will get the next passes for the location registered in your customer account. You can also check the next Astrocast satellite pass at a custom location, see Astrocast Portal - Satellite Passes.


With default configuration, the times of the satellite passes are given to you in UTC.

3. Hardware setup


10-15 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.

4. Send a message with the Astronode GUI

The Astronode GUI is a Windows application helping you to configure the Astronode DevKit.

See Astronode GUI for more information.

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.

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. 🟢



5. Retrieve your message in the Portal

  1. Wait about 2 hours* (typical current satellite-to-cloud latency).
  2. Go to the Astrocast Portal.
  3. Click on Messages in the sidebar.
  4. Find your message in the cloud.