It’s also possible to define a set of frequencies and process several SDR I/Q files at once, generating a collection of WAVE files which can then be fed into the decoding software. It can also demodulate to WAVE files, which can then be fed into your decoding software. Select a signal of interest by dragging a rectangle around it with your mouse, and sdrRewind will demodulate and play back the audio, either to your speakers or a virtual audio device feeding a decoder. This is more than adequate to see the various transmissions contained in the recording. Rather than just play back an SDR recording file, it allows you to select any of your SDR I/Q recording files, and display a waterfall of the entire file at once, as one large waterfall, with a temporal resolution of one second per line. SdrRewind may take a little more explanation. It decodes ALE transmissions from either audio fed into a sound card input (live decoding) or from WAVE audio files.
In this article, I’ll show how sdrRewind and Black Cat ALE can team up and speed up the process of finding and decoding ALE (Automatic Link Establishment) transmissions.īlack Cat ALE is a full featured multi-channel ALE decoder for Windows and macOS. Modern software can dramatically speed up the process. This works, but is a slow process, no better than monitoring in real time.
Much of the time, they play the recordings back through their SDR software. Many DXers record large swaths of the radio spectrum, and then go back to analyze the recordings, looking for signals of interest. IPhone app performs Weather and Meteorology Calculations