In September 2020 my new book Hands-on Signal Analysis with Python will be available through Springer Publishing. The old pages on Signal Analysis are therefore no longer available.
Please check the new github repository for this book, which contains all the Python source-code for this book, as well as Jupyter Notebooks containing additional material: https://github.com/thomas-haslwanter/sapy
Thomas Haslwanter, June 29, 2020