My program is written in VB.NET language under Visual Studio 2017 Community (the free edition of Visual Studio). My software does not control any external browser installed onto your Windows system, but comes with its own fully blown internal browser engine for rendering the websites. This is unfortunately also the reason why my installer downloads are hefty 53MB in size (otherwise it would be just 2-3MB, hi).

My browser module is based on the Google Chrome engine and therefore natively supporting HTML5 based audio streaming. This is also the reason why you do not need to install any Java Runtimes to see and hear the WebSDR. It will just work out of the box.

Basically my software is a slimmed down Chrome browser with some “smart” addons 🙂

The actual control of the modes and frequency setting is done by injecting Javascript into the running WebSDR server. The Javascript executes the same functions than the user would execute by e.g. typing something or clicking some UI elements. So I am not emulating a keystroke or a mouseclick, but I call the resulting server function directly.

Now, you might think how can someone just inject Javascript into a running website code? Very easy….it’s in principle the same as if you press F12 in Chrome or IE to access the Developer Tools. From there you can just open the Javascript shell and execute any Javascript commands you want on any website (e.g. call functions or read values of UI elements). And that’s exactly how CATSync works (with the exception that I do not need to do the detour via the F12 developer tools).
