Op-Amp Challenge: Measuring PH, No Code Required

June 8, 2023 by 2 Comments

When you see a project with a digital display these days, you’ll be forgiven for assuming that there’s some kind of microcontroller behind the scenes. And while that’s often the easiest way to get a project from idea to completion, it’s rarely the most interesting way.

This digital pH meter is a great example of that “no-code” design philosophy. According to [chris], the main use for this meter will be to measure soil pH in his garden, and the reason for eschewing a microcontroller was more or less for the challenge. And quite a challenge it was. Understanding the concept of pH isn’t always easy, and many a budding chemist has fallen victim to its perils. Actually measuring pH isn’t much easier, with the need to account for a lot of variables while measuring small voltages. Adding to the challenge was the fact that pretty much every skill on display here — from using KiCad to SMD soldering — was the first time [chris] had tackled them.

To amplify the voltage from the off-the-shelf pH probe, [chris] chose an LMV358A, a high-impedance FET-input version of the venerable LM358 op-amp, so as not to load down the probe. A negative temperature coefficient (NTC) resistor in the feedback path provides temperature compensation. He also designed a split power supply to provide positive and negative rails from a single 9-volt battery. The 3.5-digit LCD display is driven by an ICL7106 integrated A/D converter and BCD driver chip. Everything went into a nice-looking plastic enclosure that’s very suitable for a portable instrument.

As of this writing, the Op-Amp Challenge has officially wrapped, and there’s a slew of last-minute entries we need to go through. Check out the competition and stay tuned to find out who the judges pick for op-amp design glory!

2023 Hackaday.io Op Amp Challenge

Bye Bye Ubuntu, Hello Manjaro. How Did We Get Here?

June 8, 2023 by 117 Comments

Last week I penned a cheesy fake relationship breakup letter to Ubuntu, my Linux distribution of choice for the last 15 years or so. It had well and truly delivered on its promise of a painless Linux desktop for most of that time, but the most recent upgrades had rendered it slow and bloated, with applications taking minutes to load and USB peripherals such as my film scanner mysteriously stopping working. I don’t have to look far to identify the point at which they adopted Snap packages as the moment when it all went wrong. I’d reached the point at which I knew our ways must part, and it was time to look for another distro.

Continue reading “Bye Bye Ubuntu, Hello Manjaro. How Did We Get Here?” →

Apple Invent The Mechanical Watch

June 8, 2023 by 38 Comments

The Apple Watch has been on the market for long enough that its earlier iterations are now unsupported. Where some see little more than e-waste others see an opportunity, as has [NanoRobotGeek] with this mechanical watch conversion on a first-generation model.

What makes this build so special is its attention to detail. Into the Apple Watchcase has gone a Seiko movement, but it hasn’t merely been dropped into place. It uses the original Apple watch stem which is offset, so he’s had to create a linkage and a tiny pulley system to transfer the forces from one to the other. The rotor is custom-machined with am Apple logo, and the new watch face is a piece of laser-cut and heat treated zirconium. Even the watch movement itself needed a small modification to weaken the stem spring and allow the linkage to operate it.

The build is a long one with many steps, and we’re being honest when we say it would put our meager tiny machining skills to an extreme test. Sit down and take your time reading it, it really is a treat. Apple Watches may head to the tip after five years, but not this one!

See more in the video below the break, and of course long-time readers may remember we’ve considered the Apple Watch versus mechanical watches before.

Continue reading “Apple Invent The Mechanical Watch” →

Tree Planting Festivals, Air Cannons, Self-Burying Seeds, And The Complexities Of Reforestation

June 8, 2023 by 20 Comments

At first glance the problem of how to plant trees would seem to be a straightforward one: take a seed, jam it into the soil and let nature take its course. Or alternatively do much the same with a sapling that already got a start in a nice, comfortable greenhouse before leaving it to its own devices. To the average person this is generally the point where it’s considered a ‘done deal’, but one only has to take a look at the average survival rate of saplings out in the wild to perish that thought.

Each environment offers its own set of challenges when it comes to reforestation, which can perhaps be considered ironic as many of these trees are being planted where forests used to be, albeit centuries ago in many cases. There are the easy spots, such as flat fields, with rich soil, ample rain and mild weather, to the challenging terrain of Iceland, or mountainous terrain. Here the logistics are challenging and where once rich forests flourished, the very landscape seems adamant to reject this botanic intrusion.

Further complicating matters here are the myriad of reasons why we’re looking at planting so many new trees that it has even become an internet thing, as with the 2019 ‘Team Trees’ 20 million new trees challenge. So how did we get here, why exactly are we doing all of this, and how much of these attempts do bear fruit?

Continue reading “Tree Planting Festivals, Air Cannons, Self-Burying Seeds, And The Complexities Of Reforestation” →

Contrary View: Chatbots Don’t Help Programmers

June 8, 2023 by 67 Comments

[Bertrand Meyer] is a decided contrarian in his views on AI and programming. In a recent Communications of the ACM blog post, he reveals that — unlike many others — he thinks AI in its current state isn’t very useful for practical programming. He was responding, in part, to another article from the ACM entitled “The End of Programming,” which, like many other articles, is claiming that, soon, no one will write software the way we do and have done for the last few decades. You can see [Matt Welsh] describe his thoughts on this in the video below. But [Bertrand] disagrees.

As we have also noted, [Bretrand] says:

“AI in its modern form, however, does not generate correct programs: it generates programs inferred from many earlier programs it has seen. These programs look correct but have no guarantee of correctness.”

Continue reading “Contrary View: Chatbots Don’t Help Programmers” →

Photo of the head unit , with "Hacked by greenluigi1" in the center of the UI

Hacking A Hyundai Ioniq’s Infotainment System Again After Security Fixes

June 8, 2023 by 15 Comments

These days modern cars are nothing if not a grouping of networked software held together by bits of hardware. This is reflected not only in the rapidly increasing number of ECUs, but also infotainment systems and all-glass cockpits. For better or worse, this offers many exciting hacking possibilities, which [greenluigi1] was more than happy to explore with their new 2021 Hyundai Ioniq SEL last year. Naturally, Hyundai then proceeded to ‘fix’ these vulnerabilities, offering the exciting chance to test the Hyundai engineers’ homework, and proceed to bypass it again.

When we last left off in [greenluigi1]’s adventures, the Hyundai D-Audio 2V Linux-based infotainment system (formally called in-vehicle entertainment, or IVI) in question had been convinced to run custom applications after a fair bit of effort to get root access via the Engineering Menu and some firmware image hacking. Joyous hacking and exploration of the car’s CAN network and RPC messaging system ensued. Then Hyundai released a new firmware image, after months of silence and all old firmware images pulled from the download page.

In this new firmware image, big changes were visible right off the bat, with two different ZIP files instead of the single one from before. One of these ZIP files also couldn’t be decrypted any more with the old key. Unfortunately for Hyundai, the curse of backwards compatibility with older IVIs meant that the ZIP targeting headunits running the older firmware also contained the key for the new ZIP file.

Other changes included some further obfuscation to this key and the public key used for firmware hash verification, which also involved using a Micom RPC call via the CAN bus to obtain some vehicle specific information. Unfortunately, this is where Hyundai’s engineers seemed to have stopped copying reference code samples, and used a unique RSA private key to sign firmware images with. Fortunately, they did not bother to check whether the updater actually always verifies the signature, allowing for unsigned code to be installed.

All in all, a fascinating bit of reverse-engineering and sheer stubborn persistence, just so that the IVI that’s in your car can run the applications which you developed. We’re looking forward to the next installments in this series as the ball is once again firmly in Hyundai’s court.

Royal Navy Tests Quantum Navigation

June 7, 2023 by 33 Comments

GPS has changed the way we get around the globe. But if you command a warship, you must think about what you would do if an adversary destroyed or compromised your GPS system. The Royal Navy and Imperial College London think a quantum navigation system might be the answer.
Of course, Heisenberg says you can’t know your speed and position simultaneously. But at the real-world level, you can apparently get close enough. The quantum sensors in question are essentially accelerometers. Unlike conventional accelerometers, though, these devices use ultracold atoms to make very precise measurements using a laser optical ruler, which means they do not drift as rapidly as, say, the accelerometer in your phone. Navigating with accelerometers is well understood, but the issue is how often you have to correct your computed position with an actual reference due to drift and other error accumulation. You can see a Sky News report on the trial below. Continue reading “Royal Navy Tests Quantum Navigation” →