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Understanding the Effect of Eddy Currents on the High-Frequency Behavior of Magnetic Cores

Understanding the Effect of Eddy Currents on the High-Frequency Behavior of Magnetic Cores

The formation of eddy currents can cause problems for magnetic cores at high frequencies. To mitigate these undesirable effects, we first need to understand them.


Using Complex Permeability to Characterize Magnetic Core Losses

Using Complex Permeability to Characterize Magnetic Core Losses

In this article, we use the concept of magnetic field intensity to help explain how complex permeability models the losses of a magnetic core.


Analyzing and Improving the Ruthroff Transformer

Analyzing and Improving the Ruthroff Transformer

We analyze a Ruthroff 1:4 transformer's performance at high frequencies, then learn how to improve its bandwidth using equal-delay networks and how to redesign the circuit for higher impedance transformation ratios.


A Brief Introduction to Ruthroff Transmission Line Transformers

A Brief Introduction to Ruthroff Transmission Line Transformers

Learn how these classic RF transformers achieve broadband impedance transformation.


How to Analyze Transmission Line Transformers: The Easy Way and the Hard Way

How to Analyze Transmission Line Transformers: The Easy Way and the Hard Way

In this article, we explore two different methods for analyzing the impedance transformation ratio of a transmission line transformer.


Understanding RF Calibration Using Short, Open, Load, and Through Terminations

Understanding RF Calibration Using Short, Open, Load, and Through Terminations

In this article, we conclude our discussion of VNAs by walking through the steps of a SOLT calibration and examining the potential non-idealities of its reference standards.


Understanding the 12-Term Error Model and SOLT Calibration Method for VNA Measurements

Understanding the 12-Term Error Model and SOLT Calibration Method for VNA Measurements

The 12-term error model is a simple, effective way of modeling systematic errors in vector network analyzer (VNA) measurements. Learn about this model and an associated error correction technique in this article.


Understanding the Limits of VNA Calibration

Understanding the Limits of VNA Calibration

In this article, we compare the scope of factory and user calibration for vector network analyzers (VNAs). We then learn about the types of errors that calibration techniques can't correct.


Building a Handheld Retro Gaming Console With Local Wireless Connectivity

Building a Handheld Retro Gaming Console With Local Wireless Connectivity

In this project article, we design a handheld gaming console with wireless multiplayer functionality using ESP8266 microcontrollers. We then program a game for it with the Arduino IDE.


Introduction to VNA Calibration Techniques

Introduction to VNA Calibration Techniques

Learn the basics of how vector network analyzer (VNA) calibration techniques correct measurement errors.


How to Estimate and Enhance the Dynamic Range of a Vector Network Analyzer

How to Estimate and Enhance the Dynamic Range of a Vector Network Analyzer

This article explains how to estimate the dynamic range a vector network analyzer (VNA) needs for a given measurement, then discusses four techniques for boosting the dynamic range to the required level.


Understanding the Significance of Dynamic Range and Spurious-Free Dynamic Range

Understanding the Significance of Dynamic Range and Spurious-Free Dynamic Range

In this article, we investigate two metrics used to characterize the performance of RF test and measurement systems.


Understanding the Inner Workings of Vector Network Analyzers

Understanding the Inner Workings of Vector Network Analyzers

In this article, we explore how the signal source and receivers of a VNA enable its function.


Understanding the Guanella Transmission Line Balun

Understanding the Guanella Transmission Line Balun

Learn how bifilar coils can be used to build Gustav Guanella’s classic RF balun.


Understanding RF Power Measurement Errors in Directional Couplers

Understanding RF Power Measurement Errors in Directional Couplers

Directional couplers are valuable tools for testing RF systems. However, the finite directivity of these devices can cause measurement uncertainty. Learn more in this article.


Introduction to Transmission Line Transformers and the Bifilar Coil

Introduction to Transmission Line Transformers and the Bifilar Coil

Learn how a bifilar coil can be used to design transformers for high-frequency RF applications.


Understanding the Non-Idealities of Magnetically Coupled RF Transformers

Understanding the Non-Idealities of Magnetically Coupled RF Transformers

In this article, we’ll learn about the limitations of magnetically coupled transformers in RF applications by modeling the devices' high-frequency non-idealities.


Balun Basics and Practical Performance Parameters

Balun Basics and Practical Performance Parameters

Learn about the balun, a special type of transformer used in mixers, amplifiers, and signaling.


Introduction to the Directional Coupler for RF Applications

Introduction to the Directional Coupler for RF Applications

As part of a vector network analyzer (VNA), a directional coupler enables us to characterize a device’s performance by its S-parameters. Read this article to learn more about this important piece of equipment.


Basic Principles of the Push-Pull Class B Power Amplifier

Basic Principles of the Push-Pull Class B Power Amplifier

Learn how a push-pull Class B amplifier functions, how to calculate its efficiency, and how its performance compares to the inductively-loaded Class A design.