2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/86211Filtering of digital signals is accomplished on an Excel spreadsheet using fast Fourier transform (FFT) convolution in which the kernel is either a Gaussian or a cosine modulated Gaussian. Pedagogical examples of low-pass and band-pass filtering are provided, and the practical value of the spreadsheet is illustrated with some cases involving an earthquake record generated by a folded pendulum seismometer.12 pages, 6 figuresGeneral Physicstext