Categories

## A Review of QucsStudio

The prefix Qucs (Quite Universal Circuit Simulator) refers to a family of electronic circuit simulators that can be used for free: Qucs Original, Qucs-S and QucsStudio. All variants have a very powerful and effective graphical interface, which is even better designed than that of other paid tools. This makes this simulator very attractive for all […]

Categories

## Hilbert Transform

The Hilbert transform is a linear operation applied to real signals. In practical terms, the Hilbert transform translates into a phase shift of -90º at the positive frequencies (and +90º at the negative frequencies) that make up the signal. The relevance of the Hilbert transform in telecommunication engineering is due to its contribution in obtaining […]

Categories

## Spatial Fourier Transform vs Temporal

The Fourier transform makes it possible to obtain the components that make up a signal in the transformed domain. In the most common case, the Fourier transform of temporal signals provides the frequencies (ω) that make up the signal. Equivalently, the spatial Fourier transform, applied on a signal defined in space, provides its components typically […]

Categories

## Remote Control Car Hacking

DIY Project: Redesigning and Building the Electronic Board of a Remote Control Car. Developed and written by Niva_v_Kopirce. Christmas came and I was getting ready to give my nephew a cheap Chinese car. I always like to check beforehand if any gift containing electronic components works. It worked fine, however, I instantly noticed a few […]

Categories

## Signal Propagation in Communications

In communications, signal propagation theory studies the movement of signals from the transmitter to the receiver through a transmission medium. Depending on the characteristics of the signal and the medium, different situations may arise. In general, the cases are classified according to the type of distortion they produce in the transmitted signal. This text is […]

Categories

## Phase Velocity: Waves and Signals

Phase velocity typically denotes the speed with which a sinusoidal wave or tone moves in the medium in which it propagates. The term is coined because the velocity at which the tone moves is equivalent to the speed at which any one of its phases moves, whether it is a phase that produces a zero, […]

Categories

## Group Velocity: Mathematical Proof

The term group velocity defines the rate at which the envelope of a signal propagates in a transmission medium. This signal transmitted over the medium is obtained when a modulating signal modulates a central frequency, typically called the carrier [1]. As a result, the modulating signal and the envelope are equivalent. While the envelope propagates […]

Categories

## VFD Night Light with Attiny84

VFD Night Light DIY Project. Developed and written by Frasier Chew. Vacuum Fluorescent Displays (VFDs) have been around for over 6 decades. Although its heyday has passed in favour of other newer display technologies like the LCD, they are still being used today because of their robustness. VFDs are able to operate under a wide […]

Categories

## Curve Tracer Design for Power Tubes Testing

Curve Tracer DIY Project developed and written by  Basin Street Design. This is for all those tube amp enthusiasts and hackers out there. I wanted to build a tube stereo amp that I could be proud of. However in the course of wiring it up I found that some 6AU6s just refused to bias where […]

Categories

## Waves in Electronics and Communications

This article reviews the basic theory of waves and wave motion focusing on a practical application: electronics and communications. In addition, images and graphs of moving waves are provided to facilitate the understanding of the concepts explained. The text is organized as follows. First, waves are defined from a general and also mathematical point of […]