Op-Amp Drag Race Turns Out Poorly For 741

When it was first introduced in 1968, Fairchild’s 741 op-amp made quite a splash. And with good reason; it packed a bunch of components into a compact package, and the applications for it wer…

No Inductors Needed For This Simple, Clean Twin-Tee Oscillator

If there’s one thing that amateur radio operators are passionate about, it’s the search for the perfect sine wave. Oscillators without any harmonics are an important part of spectrum hy…

Lorenz Attractor Analog Computer With Octave Simulation

[Janis Alnis] wanted to build an analog computer circuit and bought some multiplier chips. The first attempt used apparently fake chips that were prone to overheating. He was able to get it to work…

Inside A Fake LM358

[IMSAI Guy] got some fake LM358 op-amps. Uncharacteristically, these chips actually performed well even though they didn’t act like LM358s. [IMSAI Guy] did a video about the fake chips and so…

Inside Electronic Gain Control

Normally, if you want to control the gain of an amplifier, you’ll use a variable resistor. You know, like a volume control. But what if you want to control the amplifier’s gain with a v…

Low-Cost Electret Microphone Preamplifiers

Before the invention of microelectromechanical system (MEMS) microphones, almost all microphones in cell phones and other electronics were a type of condenser microphone called the electret microph…

Listening To Bats As They Search For Food

The range of human hearing goes up to about 20 kilohertz, which is fine for our purposes, but is pretty poor compared to plenty of other animal species. Dogs famously can hear up to about 60 kHz, a…

Congratulations To Our Op-Amp Challenge Winners!

The real world is analog, and the op-amp is the indispensable building block of many analog circuits. We wanted to give you analog fanatics out there a chance to shine and to encourage our digital …

Op-Amp Challenge: MOSFETs Make This Discrete Op Amp Tick

When it comes to our analog designs, op-amps tend to be just another jellybean part. We tend to spec whatever does the job, and don’t give much of a thought as to the internals. And while it …

Op Amp Contest: Magnetic Core Memory The Dr Cockroach Way

No matter how memory technology marches on, magnetic core memory is still cool. Radiation-hard, nonvolatile, and so pretty. What’s there not to love? [Mark Nesselhaus] is no stranger to fun i…

Op-Amp Challenge: Compare Op-Amps, By Listening To Them

In the world of audiophilia there are arguments that rage over the relative merits of particular components. Sometimes this can reach silly levels as in the high-end ALPS pot we once saw chosen as …

Op-Amp Challenge: A Low Noise Amplifier For Those Truly Low Noise Measurements

When something is described as “Low Noise”, it is by the nature of the language a relative phrase. The higest quality magnetic tape is low noise compared to its cheaper sibling for exam…

Op-Amp Challenge: Get More From A Single Wire With An Analogue Adder

It’s been a running battle in some quarters for years, whether analog sensor processing is better than digital. Proponents of digital are sometimes driven by lack of familiarity with analog c…

Op-Amp Challenge: Reliable Peak Power Measurement

As part of our Op-Amp Challenge we’re seeing a wide diversity of entries showcasing the seemingly endless capabilities of these extremely versatile parts. Another one comes from [Joseph Thoma…

Op Amp Challenge: An Ultra-Cheap PH Sensor Amplifier

It’s rare in 2023 for an instrument to be entirely analog, instead it’s more normal for a front-end to feed the analog-to-digital converter (ADC) in a microcontroller. Typically the fro…

Op Amp Challenge: An Op-Amp Buck Regulator

Switching regulators have delivered such convenience and efficiency compared to their linear siblings, that it’s now becoming rare to see an old-style three-terminal regulator. Modern designs…

Op Amp Challenge: What’s Your Monitor’s Delay?

In the days of CRT displays, the precise synchronization between source and display meant that the time between a video line appearing at the input and the dot writing it to the screen was constant…

Op Amp Contest: A Slice Of The ’70s

The 1970s was a great time to be an electronics hobbyist, as a whole new world of analogue integrated circuits was coming down in price while new devices would appear to tempt the would-be construc…

Op Amp Contest: Go Down An Octave, No FFT, No PLL, No Oscillator!

We like a project that makes us think, and that was certainly the case with [MS-BOSS]’s octave downshifter that’s an entry in our current op-amp contest. Instead of resorting to an FFT,…

A High Precision ADC That You Can Understand!

In a world where an analogue to digital converter is all too often an integrated peripheral buried inside a microcontroller, it’s easy to forget how simple these devices can be when built fro…