A Quantum Magic 8-Ball

June 27, 2026 by Zoe Skyforest 27 Comments

If you ever cracked open one of those Magic 8-Ball toys, you found little more than a polyhedron floating in some dark-colored fluid. It was a quasi-random way of asking the universe to answer crucial questions like “will Mom and Dad get a divorce?” and “does Bethany like me?” even if the results were seldom accurate (sorry about your parents, kid). If you want a more reliably random 8-ball that is not even slightly more truthful, you might like this recent build from [David Noel Ng].

The concept is simple enough — leverage quantum effects that provide truly random results to seed run a random number generator that determines the outcome of a software magic 8-ball. [David] tried a few ways to build something along these lines, and eventually settled on a setup that he felt suited the task at hand.

In the final rig, a light source spits out photons, and is attenuated to the point where effectively only one photon is running through the light path at a time. Each photon passes through a beam splitter, and either passes through the mirror and hits photomultiplier A, or bounces off and hits photomultiplier B. This creates a truly random yes/no result for every photon that passes through. [David] does a great job of explaining the low-level physics at play, as well as the supporting electronics and code that turns this into a usable magic 8-ball that actually answers questions.

We’ve seen other magic 8-ball builds before, too. Few come with quite the same tactile wonder created by the original toy, but they nonetheless do the job of answering questions that are too frivolous to take to a tarot reader or local divining bog witch. If you’re whipping up your own way to deduce the wills of the fates, don’t hesitate to let us know on the tipsline.

Hackaday Links: April 27, 2025

April 27, 2025 by Dan Maloney 14 Comments

Looks like the Simpsons had it right again, now that an Australian radio station has been caught using an AI-generated DJ for their midday slot. Station CADA, a Sydney-based broadcaster that’s part of the Australian Radio Network, revealed that “Workdays with Thy” isn’t actually hosted by a person; rather, “Thy” is a generative AI text-to-speech system that has been on the air since November. An actual employee of the ARN finance department was used for Thy’s voice model and her headshot, which adds a bit to the creepy factor.

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Quantum Random Number Generator Squirts Out Numbers Via MQTT

April 26, 2025 by Zoe Skyforest 24 Comments

Sometimes you need random numbers — and properly random ones, at that. Hackaday Alum [Sean Boyce] whipped up a rig that serves up just that, tasty random bytes delivered fresh over MQTT.

[Sean] tells us he’s been “designing various quantum TRNGs for nearly 15 years as part of an elaborate practical joke” without further explanation. We won’t query as to why, and just examine the project itself. The main source of randomness — entropy, if you will — is a pair of transistors hooked up to create a bunch of avalanche noise that is apparently truly random, much like the zener diode method.

In any case, the noise from the transistors is then passed through a bunch of hex inverters and other supporting parts to shape the noise into a nicely random square wave. This is sampled by an ATtiny261A acting as a Von Neumann extractor, which converts the wave into individual bits of lovely random entropy. These are read by a Pi Pico W, which then assembles random bytes and pushes them out over MQTT.

Did that sound like a lot? If you’re not in the habit of building random number generators, it probably did. Nevertheless, we’ve heard from [Sean] on this topic before. Feel free to share your theories on the best random number generator designs below, or send your best builds straight to the tipsline. Randomly, of course!

Shine On You Crazy Diamond Quantum Magnetic Sensor

April 15, 2025 by Dan Maloney 21 Comments

We’re probably all familiar with the Hall Effect, at least to the extent that it can be used to make solid-state sensors for magnetic fields. It’s a cool bit of applied physics, but there are other ways to sense magnetic fields, including leveraging the weird world of quantum physics with this diamond, laser, and microwave open-source sensor.

Having never heard of quantum sensors before, we took the plunge and read up on the topic using some of the material provided by [Mark C] and his colleagues at Quantum Village. The gist of it seems to be that certain lab-grown diamonds can be manufactured with impurities such as nitrogen, which disrupt the normally very orderly lattice of carbon atoms and create a “nitrogen vacancy,” small pockets within the diamond with extra electrons. Shining a green laser on N-V diamonds can stimulate those electrons to jump up to higher energy states, releasing red light when they return to the ground state. Turning this into a sensor involves sweeping the N-V diamond with microwave energy in the presence of a magnetic field, which modifies which spin states of the electrons and hence how much red light is emitted.

Building a practical version of this quantum sensor isn’t as difficult as it sounds. The trickiest part seems to be building the diamond assembly, which has the N-V diamond — about the size of a grain of sand and actually not that expensive — potted in clear epoxy along with a loop of copper wire for the microwave antenna, a photodiode, and a small fleck of red filter material. The electronics primarily consist of an ADF4531 phase-locked loop RF signal generator and a 40-dB RF amplifier to generate the microwave signals, a green laser diode module, and an ESP32 dev board.

All the design files and firmware have been open-sourced, and everything about the build seems quite approachable. The write-up emphasizes Quantum Village’s desire to make this quantum technology’s “Apple II moment,” which we heartily endorse. We’ve seen N-V sensors detailed before, but this project might make it easier to play with quantum physics at home.

You Too Can Do The Franck-Hertz Experiment

March 15, 2025 by Al Williams 5 Comments

We talk about quantum states — that is, something can be at one of several discrete values but not in between. For example, a binary digit can be a 1 or a 0, but not 0.3 or 0.5. Atoms have quantum states, but how do we know that? That’s what the Franck-Hertz experiment demonstrates, and [stoppi] shows you how to replicate that famous experiment yourself.

You might need to translate the web page if your German isn’t up to speed, but there’s also a video you can watch below. The basic idea is simple. A gas-filled tube sees a large voltage across the cathode and grid. A smaller voltage connects to the grid and anode. If you increase the grid voltage, you might expect the anode current to increase linearly. However, that doesn’t happen. Instead, you’ll observe dips in the anode current.

When electrons reach a certain energy they excite the gas in the tube. This robs them of the energy they need to overcome the grid/anode voltage, which explains the dips. As the energy increases, the current will again start to rise until it manages to excite the gas to the next quantum level, at which point another dip will occur.

Why not build a whole lab? Quantum stuff, at a certain level, is weird, but this experiment seems understandable enough.

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Hackaday Links: February 2, 2025

February 2, 2025 by Dan Maloney 8 Comments

All things considered, it was a very bad week for aviation here in the United States. Three separate crashes, two of which involved US military aircraft, have left over 70 people dead. We’ll spare you the details since there are plenty of other places to get news like that, but we did want to touch on one bright spot in this week’s aviation news: the first successful supersonic flight by a US-made civilian aircraft. There are a lot of caveats to that claim, but it’s clear that Boom Supersonic is on a path to commercializing supersonic air transportation for the first time since the Concorde was retired. Their XB-1 “Baby Boom” test aircraft managed three separate supersonic runs during the January 28 test flight over the Mojave test range. As usual, Scott Manley has excellent coverage of the test flight, including a look at how Boom used a Starlink terminal and an iPhone to stream cockpit video.

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8-Bit Computers Crunch Advanced Scientific Computations

December 1, 2024 by Bryan Cockfield 37 Comments

Although largely relegated to retrocomputing enthusiasts and embedded systems or microcontrollers now, there was a time when there were no other computers available other than those with 8-bit processors. The late 70s and early 80s would have seen computers with processors like the Motorola 6800 or Intel 8080 as the top-of-the-line equipment and, while underpowered by modern standards, these machines can do quite a bit of useful work even today. Mathematician [Jean Michel Sellier] wanted to demonstrate this so he set up a Commodore 64 to study some concepts like simulating a quantum computer.

The computer programs he’s written to do this work are in BASIC, a common high-level language of the era designed for ease of use. To simulate the quantum computer he sets up a matrix-vector multiplication but simplifies it using conditional logic. Everything is shown using the LIST command so those with access to older hardware like this can follow along. From there this quantum computer even goes as far as demonstrating a quantum full adder.

There are a number of other videos on other topics available as well. For example, there’s an AmigaBasic program that simulates quantum wave packets and a QBasic program that helps visualize the statistical likelihood of finding an electron at various locations around a hydrogen nucleus. While not likely to displace any supercomputing platforms anytime soon, it’s a good look at how you don’t need a lot of computing power in all situations. And, if you need a refresher on some of these concepts, there’s an overview on how modern quantum computers work here.