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Pre-emphasis and De-emphasis Filtering in FM Systems

Pre-emphasis and De-emphasis Filtering in FM Systems

Simple first-order pre-emphasis and de-emphasis filters can boost FM receiver SNR by more than 13 dB by exploiting the spectral differences between signal and noise.


Sensibel’s MEMS Smart Optical Microphone Hits New Performance Peaks

Sensibel’s MEMS Smart Optical Microphone Hits New Performance Peaks

The new mic offers an 84-dBA signal-to-noise ratio and a 146-dB acoustic overload point—a 10-dB improvement over the industry standard.


News Sep 09, 2026 by Duane Benson
Building a 5 V Single-Supply Electret Microphone Preamp

Building a 5 V Single-Supply Electret Microphone Preamp

This project brief describes how to build a compact, single-supply preamplifier module that converts the output of an electret microphone into a usable line-level audio signal.


A Peek Inside the Electronics on the Nancy Grace Roman Space Telescope

A Peek Inside the Electronics on the Nancy Grace Roman Space Telescope

The Nancy Grace Roman Space Telescope’s mirror may get the headlines, but its detector chips, photon-counting cameras, and downlink amplifier tell the electronics story.


News Aug 31, 2026 by Robert Martin
Build an Instrumentation Amplifier with Picoamp-Level Input Bias Current

Build an Instrumentation Amplifier with Picoamp-Level Input Bias Current

Discover how the LT1079 quad op-amp minimizes sensor loading in battery-powered designs. Active cancellation and an onboard bridge network ensure maximum precision for resistive sensors.


Nuvoton Teams up With Klippel To Reimagine Smart Audio Amplifiers

Nuvoton Teams up With Klippel To Reimagine Smart Audio Amplifiers

New chip weds advanced technology from Nuvoton and Klippel to create a high-performance audio solution for smart audio devices


News Aug 17, 2026 by Duane Benson
The TL072: A JFET Op Amp That Became the Default for Audio

The TL072: A JFET Op Amp That Became the Default for Audio

Texas Instruments combined JFET inputs with a bipolar output stage in 1977—and it slowly took over guitar pedals, synthesizers, and mixing desks.


News Aug 14, 2026 by Luke James
A 60 W Class-AB Audio Amplifier: A TDA7296-Based Single-Channel Power Amp

A 60 W Class-AB Audio Amplifier: A TDA7296-Based Single-Channel Power Amp

Learn how to construct a robust DMOS-based board featuring mute and standby controls. It easily drives 4 or 8 Ω loads for your next custom stereo or speaker project.


SNR Analysis of FM Modulation with Arbitrary Message Signals

SNR Analysis of FM Modulation with Arbitrary Message Signals

Deriving a general signal-to-noise expression for frequency modulation with any message signal reveals a core trade-off: more deviation buys better noise performance, but only by using more bandwidth.


A 500 mA Power Op Amp Breakout Board With Precision Current Limiting

A 500 mA Power Op Amp Breakout Board With Precision Current Limiting

Safely drive up to ±500 mA into reactive loads. This compact module employs the LT1970A and offers independent 1% source/sink thresholds and onboard fault diagnostics.


Understanding Noise in FM Systems: The Tone-Modulated Scenario, Part 2

Understanding Noise in FM Systems: The Tone-Modulated Scenario, Part 2

This article explores how combining signal and noise power reveals how the FM system’s output SNR scales with carrier amplitude and modulation index.


A Dual 38W Power Amplifier: A Compact STA540-Based Stereo Audio Board

A Dual 38W Power Amplifier: A Compact STA540-Based Stereo Audio Board

This project brief describes how to build a compact dual-channel power amplifier module that delivers 38 W per channel into 4-ohm speakers using STMicroelectronics' STA540 audio amplifier IC.


Understanding Noise in FM Systems: The Tone-Modulated Scenario, Part 1

Understanding Noise in FM Systems: The Tone-Modulated Scenario, Part 1

Explore how frequency-modulated waves resist interference. We break down the demodulator architecture and derive the exact output signal power for a sinusoidal message.


Understanding the Noise Performance of AM Receivers with Envelope Detection

Understanding the Noise Performance of AM Receivers with Envelope Detection

Envelope detection is simple, but that simplicity has a noise-performance cost. Here’s how much SNR conventional AM gives up compared to its coherent counterparts.


An Ultra-Low-Noise Pre-Amp For Audio Applications

An Ultra-Low-Noise Pre-Amp For Audio Applications

Build an ultra-low-noise preamplifier with a JFE150 JFET and OPA202 op-amp, perfect for high-impedance sensors, hydrophones, guitar pickups, microphones, and turntables.


Analyzing the Noise Performance of Coherent SSB Demodulators

Analyzing the Noise Performance of Coherent SSB Demodulators

Using a graphical approach, we show that coherent SSB demodulation leaves the input and output SNR unchanged, then compare its noise performance to DSB-SC and baseband systems.


Understanding SNR in DSB‑SC Coherent Detection: A Graphical Approach

Understanding SNR in DSB‑SC Coherent Detection: A Graphical Approach

Visualizing how correlated and uncorrelated signals combine offers an intuitive look at power transformation. See how this difference boosts baseband power to double the output SNR.


Designing a Tuneable Ultrasonic Filter

Designing a Tuneable Ultrasonic Filter

Learn how to build a constant-bandwidth band-pass filter covering 20 kHz to 60 kHz, with an integrated frequency counter for precise tuning.


Evaluating the Noise Performance of Coherent DSB‑SC Demodulators

Evaluating the Noise Performance of Coherent DSB‑SC Demodulators

In this article, we'll learn how to calculate the noise power and signal-to-noise ratio (SNR) of a double-sideband suppressed-carrier communication system.


Class AB vs. Class D: Understanding the Trade-Offs for Piezo Driver Design

Class AB vs. Class D: Understanding the Trade-Offs for Piezo Driver Design

In this article, we explore when to choose a Class AB or Class D output stage for your piezo amplifier design. We'll also examine the Class D stage's power supply requirements.