Power factor is the ratio between the energy that is converted into work and the electrical energy consumed in a circuit or device

## Half Wave Rectifier – Half-wave Rectifier. Circuit diagram

The half-wave rectifier rectification process.

Polarization of semiconductor diode in the forward and in the reverse direction. Input and output waveforms

## Push – Pull Amplifier – Push – Pull Amplifier Operation

Push – Pull Amplifier

A Push – Pull amplifier is called that way, because it uses 2 groups of transistors and only one works at a time. One group pushes in one direction while the other pulls in another direction. Each group is responsible for amplifying a single phase of the input wave.

## Parallel RC circuit

Parallel RC circuit

Voltage, Currents, Phasor diagram & Impedance. Voltage is the same on the capacitor and resistor. Current is ahead of the voltage in the capacitor

## Sinusoidal oscillator (basic structure)

Basic structure of the sinusoidal oscillator

The sinusoidal oscillator basic structure consists of an amplifier (A) and a selective frequency network (ß) connected in a positive feedback loop

## Series RC circuit connected to an AC voltage

In a series RC circuit, the current through the resistor and the capacitor is the same. The voltage VS is equal to the phasor addition of the voltage drop across the resistor (Vr) and the voltage drop across the capacitor (Vc).

## Properties of the Alternating Current (AC)

What is Alternating Current?

The difference between an alternating current and a continuous current is that the continuous current flows only on one direction. The alternating current circulates first in one direction and then on the opposite one, repeating this process continuously.

## Resonance in an RLC Circuit

Resonance in RLC Circuits is a special condition for parallel and series RLC circuits, when capacitive reactance and inductive reactance have the same magnitude and cancel each other. This only happens at frequency fo.

## Power in AC Circuit

Electric power. Electrical power on a circuit with reactive load (reactance). How to obtain the current in a circuit having resistance and reactance.

## Impedance (Z) = (Resistance + Reactance)

Impedance (Z) shows the opposition to the flow of direct or alternating current. Impedance is the vector addition of resistance (R) and reactance (X).

## Crystal Oscillators – Piezoelectric Oscillator. Equivalente circuit

The Crystal Oscillators (Piezoelectric Oscillator) A quartz crystal has a property called: piezoelectric effect. This effect causes, by applying a mechanical pressure on the surface of the crystal, that a voltage is developed on the opposite sides. In a similar way, a voltage applied on the faces of the crystal produces a mechanical distortion on their surface. An AC voltage causes […]

## LC Oscillator – Inductance – Capacitance Oscillator

LC oscillator: Inductance – Capacitance Oscillator A simple oscillator can be built with an amplifier stage and an inductive-capacitive network (LC) to provide an offset of -180° The oscillation frequency can be freely adjusted or tuned on a range of frequencies from 100kHz to a few hundred MHz by changing only the value of C or L. These LC […]