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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.


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.


The MOS 6581 SID: Giving the Commodore 64 Its Voice

The MOS 6581 SID: Giving the Commodore 64 Its Voice

Bob Yannes built a three-voice analog synthesizer onto one die in 1982, and its imperfect filter became the signature sound of an era.


News Jul 31, 2026 by Luke James
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.


The NE565: The Chip That Made the Phase-Locked Loop Practical

The NE565: The Chip That Made the Phase-Locked Loop Practical

Signetics packed a VCO and phase detector into one 14-pin part, turning a daunting feedback technique into something an ordinary engineer could build.


News Jul 17, 2026 by Luke James
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.


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.


Microchip Ruggedizes Evacuated Miniature Crystal Oscillators

Microchip Ruggedizes Evacuated Miniature Crystal Oscillators

The EX-423 adds four-point crystal mounting, ultra-high vacuum housing, and MIL-STD-202 to Microchip's EX-421 EMXO lineup.


News May 28, 2026 by Jake Hertz
Ralph Hartley and the Origins of Digital Information Theory

Ralph Hartley and the Origins of Digital Information Theory

Whether designing modulation schemes or modeling entropy, engineers are still guided by Hartley's principle that information can and must be measured.


News May 15, 2026 by Luke James
SiTime Reveals MEMS Timing Device for AI Data Center GPU Optimization

SiTime Reveals MEMS Timing Device for AI Data Center GPU Optimization

The MEMS-based oscillator delivers less than 1 nanosecond of time synchronization accuracy for AI clusters.


News May 11, 2026 by Jake Hertz
Using Gilbert Multipliers as Phase Detectors in PLLs

Using Gilbert Multipliers as Phase Detectors in PLLs

This article explores the operation of the Gilbert-cell phase detector for both small and large signals.


Introducing the Lag-Lead Filter

Introducing the Lag-Lead Filter

Learn how using a pole-zero loop filter improves PLL performance and design flexibility over the simpler lag filter.


Understanding the Limitations of the Second-Order Type-1 PLL With a Lag Filter

Understanding the Limitations of the Second-Order Type-1 PLL With a Lag Filter

In this article, we analyze the steady-state errors and Bode plots for a second-order PLL with a simple, first-order loop filter.


Introduction to Second-Order Type-1 PLLs

Introduction to Second-Order Type-1 PLLs

Learn how adding a lowpass loop filter to a PLL with a single integrator impacts both the frequency-domain and time-domain response.


SiTime Introduces Jamming- and Spoofing-Resistant Precision Oscillator

SiTime Introduces Jamming- and Spoofing-Resistant Precision Oscillator

With an eye on aerospace and defense applications, SiTime designed the new oscillator—announced today—with multi-layer reliability for GNSS receivers.


News Dec 03, 2025 by Duane Benson
Analyzing First-Order PLLs Using Linear Models

Analyzing First-Order PLLs Using Linear Models

In this article, we'll use the linearized model of a first-order PLL to understand its response to a simple input change. We'll then use Matlab simulations to visualize the signals.


Analyzing a First-Order PLL in Acquisition Mode With a Nonlinear Model

Analyzing a First-Order PLL in Acquisition Mode With a Nonlinear Model

In this article, we'll use a nonlinear mathematical model to improve our understanding of how a first-order PLL locks to a signal.


FM Generation Techniques: Solved Examples

FM Generation Techniques: Solved Examples

In this article, we'll solidify our understanding of the reactance modulator and Armstrong modulator circuits by working through a series of design problems.