Inmarsat L-Band WebSDR

Web SDR working Inmarsat-4 (Alphasat) 25 East and Inmarsat-3 54 West from grid square JN58UA using L-Band RHCP 7 turn and 10 turn helix antenna respectively.

  • SDR1 -> QO100 / Es’hail-2
  • SDR2 -> Inmarsat-4 AF1/Alphasat 25° East
  • SDR3 -> Inmarsat-3 F5 54° West


You can access this groundstation remotely and test it yourself. Install JAERO and hook up to the websdr via virtual audio cable. Send me some screen shots of your decoded data streams.

Want to build your own station?

Checkout the 3D printed L-Band antenna driving this setup.

L-Band products are available here: