Rubén Sánchez

Frequency aliasing (or folding)

In the following Python script it is shown how the aliasing effect (having signals whose frequency is beyond half of the sampling frequency, i.e., …

Charge sharing in series and parallel capacitors

Motivation

Several months ago I started trying to find how charge distribution across different capacitors works and I came up to this thought …

Visit all array combinations with a recursive function

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A = [ …

Can't login Elementary OS after changing icon set

After trying to change the default icon set in Elementary OS, I was not able to log in again into the desktop. This happened to me after installing …

Transfer data from Android to PC using rsync

1. Install SimpleSSHD in your mobile

2. In order to start data transfers, you can use the rsync command which has the following syntax:

rsync …

Thevenin's theorem

Introduction

Any two-terminal network whose internal circuitry is made up solely of resistors, current sources and voltage sources can be simplified …

Current source and switched capacitors in parallel

A capacitor is an electronic device able to store electrical energy in an electrical field. Usually, the capacitor is defined in its most simple …

DFT as a change of basis

DFT can be thought as a simple change of basis. In the time domain, every sample of a signal represents its amplitude at that very instant.

\[ y\left …

Romancero bot: converting article text into voice with Amazon Polly and sending it to Telegram

The following Python script extracts the content of an article using Readibility (ported to Python), converts it to voice using the Amazon Polly …

Parser in PHP using regular expressions

You can use regular expressions in PHP with the function preg_match ( string $pattern , string $subject