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A full featured program that decodes and displays NAVTEX and SITOR-B maritime transmissions on shortwave radio, available for macOS and Windows.

Tune your HF / shortwave radio or SDR to a NAVTEX or SITOR-B frequency and feed the audio into your computer's sound card input, and start receiving and displaying transmissions in minutes.

Works great with SDR software and virtual audio cables! Run up to 8 NAVTEX SITOR-B decoders in parallel at the same time, each tuned to a different frequency.

You can change the color scheme and font type/size to your preferences.

Black Cat NAVTEX SITOR-B is available for download and trial prior to purchase, so you can make sure it works correctly with your setup. It's available for Windows 8 10, and 11 (Windows 7 is not supported) as well as macOS.

The main window displays recently received messages along with a convenient and thoughtfully arranged user interface (click on any image below for a full sized version) with decodes from each frequency both separately shown as well as combined into one view:

There's also a schedule window, so you can easily see what transmissions are on the air now, or are upcoming:

Buy Your Copy of Black Cat NAVTEX SITOR-B Today

Start decoding NAVTEX SITOR-B transmissions in just minutes!

$29.99 Registration code sent by email, software download

Black Cat NAVTEX SITOR-B is only $29.99 (Introductory pricing). Purchase also entitles you to all updates and new versions released over the next full year, free of charge, which of course you can continue to use forever.

Free To Try!

Not sure you're ready to buy Black Cat NAVTEX SITOR-B? You can (and should!) download a fully featured copy to try out, before you buy it.

Download a copy of Black Cat NAVTEX SITOR-B version 1.0.0 for Windows 8, 10, 11: Black Cat NAVTEX SITOR-B 1.0.0 for Windows - Windows 8 / Windows 10 / Windows 11 - 8 May 2023

Download a copy of Black Cat NAVTEX SITOR-B version 1.0.0 for macOS 10.10 and later, 64 Bit Application: Black Cat NAVTEX SITOR-B 1.0.0 for Mac OS X - Mac OS X 10.10 and later - 8 May 2023

If macOS complains it cannot open the app, right click the app icon, and select Open.

A virtual audio cable/driver is required for use with SDR programs. We have a list of third party programs here.
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Last modified May 8, 2023