Stavros' Stuff 2 days ago

I made a voice note taker

Have you ever always wanted a very very small voice note recorder that would fit in your pocket? Something that would always work, and always be available to take a note at the touch of a button, with no fuss? Me neither. Until, that is, I saw the Pebble Index 01 , then I absolutely needed it right away and had to have it in my life immediately, but alas, it is not available, plus it’s disposable, and I don’t like creating e-waste. What was a poor maker like me supposed to do when struck down so cruelly by the vicissitudes of fate? There was only one thing I could do: I could build my own, shitty version of it for $8, and that’s exactly what I did. Like everyone else, I have some sort of undiagnosed ADHD, which manifests itself as my brain itching for a specific task, and the itch becoming unbearable unless I scratch it. This usually results in me getting my phone out, no matter where I am or who I’m with, and either noting stuff down or doing the task, which some people perceive as rude, for inexplicable reasons that are almost certainly their fault. Because, however, it has proved easier to just not get my phone out in polite company than convince everyone of how wrong they are, I just do the former now, but that makes the itch remain. Also, sometimes I’m just in the middle of something, and an idea pops into my head for later pursuit, but I get distracted by a squirrel, a car going by, or the disturbing trend of the constant and persistent erosion of civil rights all over the world, and I forget the idea. The Pebble Index showed me that there’s a better way, a device that’s unobtrusive, available, and reliable enough that I could just press a button, speak into it, and know for sure that my sonorous voice would reach the bowels of my phone, where it would be stored safely until I was bored and wanted something to do. I didn’t want to have to get my phone out, unlock it, open a voice recorder app, hold down a button, speak, wonder if it heard me, look at the button, realize I had already pressed it, press it again, say the thing again, press it again to stop, exit the app, lock my phone, and put it back into my pocket. I wanted to take a thing out, press a button, speak, release the button, done. The initial thinking was that I’d use a microcontroller (an ESP32 is my microcontroller of choice these days), a microphone, and a lithium battery, and that’s basically all the hardware this needs! Most of the heavy lifting would need to be done in software. This would need: Luckily, I know enough about electronics to know that LLMs would definitely know how to build something like that. Indeed, Claude confirmed my suspicions by saying that all I need is a microphone and an ESP32. It recommended an ESP32-C6 but I went with an ESP32-S3 , as it had an onboard charge controller and would be able to charge a lithium battery from USB, which is very handy when you’re making a thing that runs on battery. The ESP32 is a microcontroller, a little computer that’s just really small. The main difference of the S3 from the C6 is that the S3 is more capable, and has more power. I keep an assortment of random components around, so I had an ESP32-S3 board. It’s a no-name, crappy one from AliExpress, not a good, Seeed-branded one from AliExpress, but it would have to do. Unfortunately, I didn’t have a MEMS microphone (which is basically an angelic grain of rice that can hear, with excellent quality), but I did have an electret mic, which is huge and bad quality and would sound like an old-timey radio, but it was there and it was ready and it was willing, and after a few beers it seemed like it was right, or at least right for right now. I also had a very thin LiPo battery, which would suit very well. For the final device I’d want a battery that’s a tiny bit shorter, as this one was around 40% longer than the ESP32, but it would do great for now. I quickly soldered everything together and recorded some audio. It worked! It worked and nobody was going to take that from me, even though it was crackly and the quality wasn’t great. Unfortunately, at this stage I realized that the analog electret microphone consumes too much energy, even when sleeping, which is terrible on a device that would spend more time sleeping than the beauty from that fairytale, Sleepy the Dwarf. To counteract that, I decided to use a MOSFET to cut power to the mic when the device was asleep. A MOSFET is a little switch that you can turn on and off from a microcontroller, basically. Full disclosure here, before using the MOSFET to turn the mic on and off, I went down a multi-hour rabbit hole trying to design a latching circuit that would allow the ESP32 to turn itself off and consume almost no power. Instead, it consumed a lot of my time, without anything to show for it, because I didn’t manage to make it work at all. The MOSFET for the mic worked fairly well, though, and the device didn’t consume much power when asleep. The real gains, however, were going to be had when the MEMS microphone I ordered arrived, as those use infinitesimal amounts of current when asleep, and have much better sound quality as well, as they are digital. The analog microphone crackled and popped and took a while to stabilize after boot, which was unfortunate because I wanted the device to be ready as soon as the user pressed the button. There was also a recording bug where the recording was missing a few milliseconds of audio every so often, which led to dropped phonemes and words sometimes sounding like other words because parts of them were dropped. All these problems were weird enough and hard enough to debug that I resolved to just wait for my digital MEMS microphone to arrive, which would solve them in one fell swoop, as it is digital and amazing. After the relatively easy part of connecting a few wires together, now came the hard part: Designing a case for the whole thing that would fit without leaving much empty space, to make the device as small as possible. This was very hard to do with this massive microphone that was as tall as everything else (including battery) combined. I initially tried to point the microphone downward while mounting it at the top, so it would take up the least amount of vertical space possible, but the PCB made that hard, as the microphone was soldered to it. I ended up desoldering the mic from the PCB, trimming the PCB to make it shorter, and connecting the mic to it with wires. That allowed me to make the case (and thus the device) smaller, but at what cost? Nothing, turns out, because it worked great. The device was working great, but I didn’t want it tethered to my computer, I wanted to be able to take it out and about and show it the wonders of the world. To do this, I needed Bluetooth. Unfortunately, I have exactly zero idea how Bluetooth works, and would need to spend days or weeks figuring stuff out, but, luckily for me, I had a Claude subscription. It took a bit of back-and-forth, but I did manage to end up with a Python script that would connect to the pendant, download the audio files, and convert them from ADPCM to MP3, for expanded compatibility. To maximize battery life, the way things worked was: This worked really well, the device was awake for a small amount of time (10 seconds), but it could be awoken at any time just by tapping the button. At that point, it would transfer to the PC any files that were on the pendant, and go back to sleep. One downside was that transfers would take an inordinate amount of time, sometimes reaching 2 minutes for a 10-second clip. OpenAI’s Codex was really helpful here, finding a solution for fast BLE transfers that made sending files 100x faster than it was before. Because I’m too impatient to wait for the slow boat from China, I ordered the same microphone locally. I had to pay an arm and a leg in shipping and impatience fees, but it was worth it, because I finally had a MEMS mic! It’s so cute and tiny, I immediately found a spot for it over the board, added the switch, added a voltage divider for sensing battery voltage, and that was it! The new mic sounds fantastic, it sounds better than recording with your phone, for some odd reason that I’m sure is all in my head. What’s more, it doesn’t have the weird bugs that plagued me with the analog mic. With this smaller mic, I could now design a better case. I designed the case you see on the right, which is the second generation. There will be a third, when I receive the shorter battery, which means I will have a choice of either making the device longer but half as thick, or around 40% shorter. I think I will go for longer but thinner, I’d quite prefer to have a thin device in my pocket, even if it’s long, than a stubby one that pokes out. Still, the new battery (and the new case) will mark the completion of this project and make me a very happy man. For the second-gen case, I decided to jazz it up and add a red stripe around it, because it was easy to do and because I think it looks good. Unfortunately, the feature I wanted most (fillets, i.e. rounded corners) wasn’t possible due to the lack of empty space inside the case. I hope the final device will have some more space for fillets, at least. Once I was done with the device, it was time to make it more ergonomic: I’d need to create an Android app so I wouldn’t have to wait to get to my PC. I also knew I wanted note transcription, as it’s really useful to be able to see what you said without having to listen to the audio again. Unfortunately again, I have no idea about Android development, only having written a small app years ago. Fortunately, though, Claude turned out to be pretty good at it, and one-shotted this app that you see here. For the transcription, I used GPT-4o Transcribe, which is great and understands both English and Greek, languages I fail to speak in equal measure. I have to say, it’s pretty magical to speak into a little box and to see the audio already captured and transcribed on your phone. With the Android app, I could now test the device in real-world use. One thing I noticed is that battery dies way too fast. I suspect that has something to do with the cheap board, so I’ve ordered an original Seeed Xiao board, and I hope that will fix the problem once and for all, as they advertise low power usage and they’re a trustworthy brand. I also added a “webhook” convenience function to the Android app, so that the latter would be able to send the transcription to a server for further processing. The device is extremely reliable, which makes me a lot more likely to use it. I know that, if I press the button, the audio will be recorded and stored, and nothing will happen to it, which makes for a very relaxed and calming experience. Before I continue, I want to say you can find all the files in this project (firmware, Android app, whatever else) in its GitHub repository: https://github.com/skorokithakis/middle That’s right, I called it Middle, because it was the next thing after the Index. I know it’s a silly name, I don’t care, don’t use it, I’m not changing it. In the “draw the rest of the fucking owl” portion of this article, I realized I didn’t want the notes to just go to my phone when LLMs exist. I wanted an LLM to take the notes and do something with them, so I spent a few weeks writing an AI agent that’s more useful than what currently exists. The device’s Android app sends the transcribed text to this AI, which processes it. I’m going to write another post about this, but basically, I wanted an AI personal assistant that could help with all the little chores in my life. AI assistants are interesting because they’re: This means that, when everyone inevitably asks “what is it good for”, I can’t really give a good answer, because the answer is “it takes care of all the little annoyances for me”, but nobody has the same annoyances and can’t really imagine what the bot does, so they don’t engage with it. The amazing thing for AI assistants for me is the fact that they can string together multiple (otherwise small) tools to do something that’s more valuable than the sum of its parts. For example, I asked the agent to give me a daily briefing every morning, consisting of my todos for the day, my calendar events, whether any refund has hit my bank, and whether any packages are due to be delivered today. The agent also checks my gym bookings and asks me every morning if I do plan to go, or if I intend to cancel. If I tell it to cancel, it does, but if I say I’ll go, it sets an alarm for a few minutes before, which I’m much more likely to see than my calendar’s one. It will also (entirely of its own volition) mention things like “you have a gym booking today 7-8pm but you have a restaurant booking at 9pm and it’ll take you more than an hour to shower and make it”, which a regular calendar wouldn’t be able to figure out. I’ve made it fantastically secure, everything is sandboxed and you can run it on your laptop without fear. I use it constantly throughout the day for many little things, and the integration with the device takes the whole setup to another level. You can find the bot here: https://github.com/skorokithakis/stavrobot Do let me know if you try it, it’s like OpenClaw but won’t steal your data and eat your firstborn. If you have any ideas, feedback, flamebait, or whatever, you can Tweet or Bluesky me, or email me directly. A way for the device to record audio onto some sort of persistent storage, for the case where you didn’t have your phone close to you. A way for the device to sleep, consuming almost no power, until it was woken up by the button. A way to transfer the files from the device to the phone, for later listening. A battery indicator would be very nice, so I knew when to recharge it. You pressed the button. If you held it down for more than half a second, the recording would “count”. If there was a recording made (i.e. if you held the button down long enough), it would be saved. Bluetooth would turn on and look for a phone or computer that’s ready to receive. The device would send the file and go to sleep again. Very open-ended tools, and Highly personal.

Python Hardware Electronics

Circus Scientist 3 weeks ago

SmartPoi Accelerometer Controller

Connects to your Poi Gets a list of images available Every time it stops spinning sends a “Change Image” signal to the poi* *only works for the newer SmartPoi firmware with Single Image selection. Code is on GitHub: https://github.com/tomjuggler/SmartPoi_Accelerometer_Controller – includes all install instructions needed (ESP32 C3 only – PlatformIO firmware). Extra: Battery, charger and switch, for one you can clip onto poi.. The post SmartPoi Accelerometer Controller appeared first on Circus Scientist . ESP32 with C3 chip: recommended: https://www.aliexpress.com/item/1005008593933324.html (just choose the correct one with antenna). I used C3 SuperMini which also works (WiFi not the best though), my better ones are still in the post. MPU-6050 Accelerometer: https://s.click.aliexpress.com/e/_c40exNFh

HTML Electronics Open Source Hardware

Brain Baking 3 weeks ago

Creating Buttons To Remember Things

My wife recently bought a device to scratch her creative crafting itch: a button press . At first, I dismissed it as yet another thing requiring space in her increasingly messy atelier. I don’t know how we manage to do it but we seem to be experts in gathering things that gather things themselves: dust. But now that she finally started doing something with it, I was secretly becoming interested in what it could mean for our scrapbook making. The button press in question is a “We R Makers Button Press Bundle All-In-One Kit” that comes with press, a few add-on peripherals that allow you to modify how it cuts and presses, and of course the buttons themselves. The button press in action, about to create a 'little monster'. Since handling the lever requires a bit of pressure to correctly cut and a second time fit the cut circle inside the button, I yelled TSJAKKA every time she would press it, to great joy of our daughter. She now calls it the Tsjakka . “Daddy, can we make another little monster with Tjsakka?” Because my first instinct after thinking about what kind of buttons I wanted was to print a variant of the Alien Lisp Mascot —a green monster with five eyes. Fellow nerds reading this might have covered their entire laptop back with cool looking stickers: a Docker container sticker, an IDEA logo one, the GitHub Octocat, and god knows what else you managed to nab from a conference table. While I always found those laptops to be just cute, I never wanted to soil mine with a sticker of some technology stack that I would grow to hate a few years later. Thanks to a random takeover by Microsoft sharks, for instance. *cough* Give Up Github *cough*. So why not a programming language mascot? Java’s The Duke? No way, I’m not that big of a Java fan. The Gopher perhaps? Better, but no. If I was to wear a badge, smack on a sticker somewhere prominent, it would have to be of something that makes me happy. Go is cool but boring. Java brings in a lot of money but smells like enterprise mud. So far, I haven’t encountered a single programming language that truly makes me happy. But Lisp is coming very close. The Lisp Alien it is, then: The result: three buttons pinned to the inside of my bike bag. One of the other two buttons is self-explanatory: the Brain Baking logo. The first one on the upper left is a part of my late father-in-law’s master’s thesis; an electronic schematic with resistors. The embossed logo on the button press, below the We R name, reads: Memory Keepers. Which is exactly what that button is for. They market it as a way to permanently record precious memories—and wear them on your sleeve . I think it’s brilliant. We don’t have an endless supply of metal clips and plastic caps to press that memory in so we have to be mindful: which one’s do we really want to create? Sure you can buy more and it’s not expensive, but that’s not the point. The point is that there won’t be a Duke on my bag, but there will be a Brain Baking logo. And, apparently, a warning. Most folks pin these buttons onto the obvious visible part of their bag. But I don’t want to come across as a button lunatic (at least not at first sight). A more convincing argument then: the bag I pinned it on is a simple detachable laptop cycle bag . The exterior gets wet now and then. I highly doubt that the button is water resistant. The third but slightly less convincing argument is that the buttons rattle quite a bit as the needle on the back used to pin it onto something sits quite loose in its metal socket. Perhaps that depends from product type to type. As you might have guessed, our daughter now is dead set on pinning a little monster on her bag she uses carry her lunch go to school. We’ll first have to ask Tjsakka to get back to work. Related topics: / crafting / By Wouter Groeneveld on 7 February 2026.  Reply via email .

Design Electronics Hardware Java

Stephen's Site 3 weeks ago

Building a 24-bit Arcade CRT Display Adapter, From Scratch

Tutorial Electronics Hardware

./techtipsy 3 weeks ago

Meet the Garbage PC

This is the Garbage PC. Not too long ago, I received a half-broken Dell Inspiron N5110, sporting 6 GB of RAM, a dual core Intel i3-2110M, and an unsupported NVIDIA GPU of some sort. One of the hinges was loose from the case because it was screwed into plastic (common issue for these types of laptops), the touchpad did not work, and to insert a drive into it, you had to disassemble the whole machine. I’m quite confident that I’ve worked on this laptop model in a very distant past, around 2012-2013, and I remember it well because during the disassembly plastic bits were falling off everywhere and the right hinge was broken in exactly the same way. I’ve always wanted to take a half-broken laptop and to mount it on some acrylic panels (plexiglass) using brass standoffs. I love how bare PCB-s look. They’re just so damn cool, and I can’t be the only one who thinks this way, right? I also get a good feeling out of taking trash/obsolete parts and making them useful once again. This laptop was destined for the e-waste pile, which meant that it was a fantastic candidate to try this idea on. The main constraint in this project was time. I’m a parent, I have a job, and sometimes between all that I like to rest, so the amount of available time for this project was about 8 hours spread across a month. I also lack proper tooling to do a good job, so this was achieved using whatever I had available, mainly a cordless jigsaw and a hand drill. On the upside, this means that if I can do it, then you can likely do it as well! This laptop turned out to be a total pain to work on. During initial testing, it was very clear that the laptop needed a good thermal paste and pads replacement, as it tried to overheat playing casual videos off of YouTube. After I disassembled the laptop to bare essentials and put it together as a test run for the “mount it on acrylic panel” idea, the extension board containing two USB ports and the Ethernet port just stopped working. I probably broke something, but annoying nevertheless. On the positive side, the overall size of the build was smaller as a result of this happy little accident. Using this laptop via the HDMI output only also turned out to be an unnecessary headache. LibreELEC did not play well with it, often resulting in a blank screen, and on Fedora Workstation 43, there was a “ghost” display somewhere that always showed up on the display settings view. So did the internal display, even when it was disconnected. This caused an issue when trying to get Fedora installed on this machine, as the installation UI would be placed on a screen that was not the HDMI output one that I was actually using. This issue can be mitigated similar to my LattePanda V1 adventure by disabling video outputs completely. For this laptop, I modified kernel parameters via and added the following kernel parameters: Yes, it’s possible to modify the display setup on your desktop environment of choice to disable certain outputs that way, but using kernel parameters ensures that if you change monitors, you won’t have to do that all over again. To make this whole build even more garbage-tier, I used an 256GB SATA SSD with 5 known bad blocks. I sourced a large 4mm thick plexiglass panel from a hardware store, as that seemed to be the most accessible place where I can get one. In Estonia, these types of panels are often sold in the gardening sections of general hardware stores. For attaching the motherboard to the board, I sourced an assortment of M2.5 brass standoffs and screws, and multiple sets in case I need more of a specific height (turned out to be a good call on my part). I chose M2.5 because the laptop used screws of that size, and this size is common in the world of Raspberry Pi and other SBC-s, which can be handy for any future dumb ideas experiments. To mark the positions on the plexiglass, I put the motherboard assembly on it, marked some good spots with an awl 1 , and then drilled holes using a hand drill and 2.5mm drill bit. I also sourced heat inserts so that I can melt them into the plexiglass assembly, but those didn’t work out very well. I used my Pinecil soldering iron to push these in to the 2mm pre-drilled holes that I set up for these, but I had alignment issues and the threads ended up getting gunked up by the melted remains of the plexiglass, so I could not screw any brass standoffs in there. I tried to be very careful with getting the drill holes to line up, and it went mostly alright. My recommendation here is to be precise, and don’t screw everything tight before you’ve got screws and standoffs lined up for all planned holes, otherwise you lose the option of wiggling things a bit to get them to line up. The standoffs and screws were screwed on tight enough to keep things in place, but not too tight to avoid cracking. For the other panel, I cut out a similarily sized plexiglass panel, marked the holes again, and repeated the process. Since I was using a cordless jigsaw, I positioned the new piece so that the flat side of the plexiglass panel that I bought lined up with the other straight end on the existing assembly, because I will never get a good straight cut with a freehanded jigsaw. That worked out well enough. For the power button, I reused the small PCB that contains the power button and power LED-s from the original case. To house that, I drilled a small hole with 1cm diameter to slip the ribbon cable in, and I used small pieces of 3M VHB double-sided tape 2 to secure it to the panel. And there you have it, the garbage PC. The shine of the plexiglass does a fantastic job of bringing out the beauty of the motherboard and all its components. Standoffs leave plenty of room for the machine to breathe. Since the extension board is missing, this build relies heavily on one USB port and one eSATA port that also supports USB connectivity. WiFi, Bluetooth, keyboard/mouse, it’s all over USB 2.0 ports. One thing that I have yet to do is to add a base to the build so that it does not tip over that easily. Double-sided tape plus a wooden trim piece might do the trick. This build is using parts that are about 15 years old. For context, that was when dubstep was popular, it was cool to hate on Justin Bieber, rage comics and bad memes were a thing, and the news in Europe were worried about Greece going bankrupt or something. That does mean that the performance on this machine is not great. The machine still runs warm, but not nearly as hot as before. In its stock form and before any thermal paste replacements, it ran about 85+°C, but now it doesn’t seem to ever hit 70°C. As a basic desktop PC, assuming that you’re not trying to run a 1440p or 4K display, the experience feels completely usable! If you’re thinking about setting this up as a media player PC, then you’re limited to H.264 playback. H.265 was just too much for this machine. If you use Kodi with Jellyfin, then it is luckily possible to enforce transcoding content to H.264, ensuring a smooth experience on the client side. I wish that this laptop supported a “power on with AC attach” type feature that turns the laptop on once the power adapter is connected, that would’ve made it more useful as a crappy little home server. If you don’t mind extended downtime during a power outage, then it can still do that job well enough, but it’s just something I was slightly annoyed with. The board has a small SATA port that can be converted to a normal SATA port, plus an eSATA port, making it perfectly plausible to add two drives to this and to totally turn it into a home server. I tried running Windows 11 on it once, but I tried to do that with the official installer and didn’t get past the “lol your hardware is too old” view. I know that you can remove that limitation, but given the 6GB of RAM and Windows 11 being awful with using resources, it was probably for the best to give up here. The fan is audible when doing things. I did in fact take it apart and added some silicon oil inside the center to give it a fighting chance and it did improve the acoustics, but it’s something to keep in mind if you’re doing similar projects with these old laptops. There does seem to be a way to control the fan by writing values to kernel module controls in , and if you overwrite the value often enough, like in a 0.1 second loop, then you can definitely overpower the BIOS fan control on this board. The control does not seem to be fine-tuned, it’s either off, on, or full speed, but at least you can get some control over the fan speed if you really need to. Alternatively, you can slap a huge heat sink on the CPU and GPU if you want to, and you should be getting away with it. The CPU throttles heavily once you hit 80°C while playing back video, so that seems to be the soft temperature ceiling for this laptop. Overall, I’m happy I did this project. There were way more obstacles and challenges associated with this project that I expected, but the end result looks cool, so that makes it worth it in my view. It was also a good trial run to work with plexiglass and brass standoffs, and I will very likely do something cooler in the future based on this experience. I hope that this inspires more people to reuse older hardware instead of just throwing it into the e-waste pile, especially with new computer parts sometimes experiencing price spikes due to the economy doing weird things. If you’ve built something similar, then do share a link to it (ideally in blog post format) and I will happily link to it here! this is the first time I actually have referred to this tool in English. What a weird word.  ↩︎ it’s good, but it smells like microplastics and cancer.  ↩︎ this is the first time I actually have referred to this tool in English. What a weird word.  ↩︎ it’s good, but it smells like microplastics and cancer.  ↩︎

Electronics Hardware

Daniel Mangum 4 weeks ago

Making Ferrite Core Inductors at Home

I have recently been working on tuning circuits, which typically consist of an inductor and a capacitor (i.e. an LC circuit). For those not familiar with inductors, they are passive components that store energy in a magnetic field. They oppose changes in current, meaning that they pass direct current (DC) and block alternating current (AC). While there are many types of inductors, ferrite core inductors are useful because the high magnetic permeability of ferrite leads to a significant increase in induction.

Jeff Geerling 1 months ago

Ode to the AA Battery

Recently this post from @Merocle caught my eye: I'm fixing my iFixit soldering station. I haven't used it for a long time and the battery has gone overdischarge. I hope it will come back to life. Unfortunately, there are no replacements available for sale at the moment. Devices with built-in rechargeable batteries have been bugging me a lot lately. It's convenient to have a device you can take with you and use anywhere. And with modern Li-ion cells, battery life is remarkable.

Hardware Electronics UI

@hannahilea 1 months ago

Telegraph Key(singular)board: Morse for the modern era

.... .- ...- . / -- --- .-. ... . / .-- .. .-.. .-.. / - .-. .- ...- . .-.. / ... - --- .--.

James Stanley 1 months ago

Tractor

The electric tractor is finished! I have been working on this on and off for about 6 months. It is a toy for children (and me) to drive around the garden. Building the tractor has been fun for both me and Lucy. On many occasions she has asked "can we go and work on the tractor? right now?" and the two of us would go out to the garage and tinker with whatever was in progress at the time. Often she would get bored and go back in the house quite quickly, but that's par for the course for a 3-year-old. With any luck some of the philosophy of creation will rub off. The tractor is powered by a 350W brushed DC motor with a 36v Li-ion ebike battery. You may be thinking that 350 watts doesn't sound very powerful, and you're right. It is a toy for children to drive around the garden, being slow is a feature not a bug. The rear axle is solid, meaning the two rear wheels always turn together. The front axle pivots around a pin in the centre, which keeps all 4 wheels on the ground when driving over uneven terrain. It has a cable-operated disc brake on the rear axle which is very ineffective, but slightly better than not having a brake at all. The seat position is adjustable, so that adults can just about squeeze on to it and toddlers can just about reach the pedals. And the tractor has very poor handling characteristics if you're an adult, because all of your weight is over the solid rear axle and the rear tyres have much more grip than the front, so you have to lean forwards to make it steer. For a while I had one of the rear wheels free-wheeling, which makes it steer better, but means it sometimes gets stuck on hills where you can't drive forwards, you can only wheelie to the side, which on balance is worse. I expect it's not as bad for small children because they're a.) not as heavy, and b.) sitting further forwards anyway. The core of the chassis is a plywood box which is open at the bottom. In this picture you can see the pin that the front axle pivots on: And you can see the pencil lines that roughly show the limits of motion of the lower edge of the axle beam. I believe the front wheels are for a sack truck, this sort of thing: They are very cheap, a pair of wheels with tyres and hubs and bearings (brand new) on eBay is only £12 including postage. I tried to copy the steering arrangement from a Ferguson TE20, which originally was my reference design for the canonical tractor, although I obviously went over to the dark side with the colour scheme. The TE20 steering wheel goes down to a gearbox quite near the driver, a shaft comes out each side, one turning clockwise and the other anticlockwise (as viewed from one fixed reference side), an arm off each shaft holds one end of a track rod, and the other end of the track rod is connected to an arm on the stub axle kingpin thing. Highlighted in red here: To replicate this I made a steering gearbox using angle grinder gears. (The yellow one is a test print - the final one is in black Polymaker PC-Max material with heavy wall thickness and lots of infill). Angle grinder gears are available cheaply and are a good way to buy high-quality bevel gears in about a 3:1 ratio, if you don't need them to be particularly heavy duty. One issue with my steering gearbox is that there is no way to install it in the chassis because the shafts stick out the sides. This was an oversight, in CAD there is no difficulty. The solution is to assemble the parts in place inside the chassis. This is inconvenient in the extreme and if I were to do it again I would try to make it removable. The arms that mount on the shafts are made of 3mm thick mild steel flat bar, bent around a rod, and then drilled for a mounting hole for the rod end, and drilled and cut to make a split-clamp for the steering shaft and kingpin. This is effective and relatively easy to make, doesn't even require any machining, I'd do this again. The only drawback is that there's not a convenient way to key it to the shaft. Originally I was planning to figure out a way to key it to the shaft after I had got the steering geometry sorted out, and therefore after I knew the angle that it wanted to be keyed at, but I have since realised that having these joints able to slip in the event of a crash is an "engineered failure" that prevents destroying the plastic gearbox. So I'm leaving it as it is. I made the steering wheel myself. It consists of 2 CNC aluminium parts, one is just a ring, and the other is the 3-pronged part for the centre of the wheel. The 3-pronged part is then bent so that the prongs sit at the right diameter, and then the 3d-printed grips are added each side, with a bolt on each prong holding the whole stack together. It is relatively flimsy, I probably wouldn't do it this way again. The rear wheels are ride-on lawnmower rear wheels. They fit a 19mm axle, which annoyingly is not a size that I was able to buy cheap pillow block bearings for. In hindsight, maybe they actually fit a 3/4" axle and it would have been easy? In any case, I don't want to deliberately construct objects with imperial measurements, that's just trouble for everyone. So instead I went with a 20mm axle, and 20mm pillow block bearings, but turned the ends down to 19mm to suit the wheels. I thought this would be easy because I was labouring under the misapprehension that a 20mm shaft would fit through the spindle bore on my mini lathe. It does not! It's very close, but it doesn't fit. Possibly you could bore out the spindle bore slightly so that it would fit, but I didn't think of that at the time, and probably it is hardened. So it can't go through the spindle bore. And the axle is too long to support the loose end with the tailstock on my lathe. So my solution was to support the loose end with a plastic bush in a piece of wood clamped in the vice, and kick the tail end of the lathe around to square it up until it's not turning a taper. This actually worked very well and I ended up with a taper going from 18.94mm to 18.97mm over 150mm length, which for all I know is as parallel as I turn anything at the best of times. See this video clip . And then the only part I can't turn down to 19mm is the tiny bit at the headstock end which is clamped in the collet, which I filed down to match the 19mm diameter after I was finished with the rest of it. The rear wheels have 2 flats in their bores to key them to the axle. I machined matching flats on the axle with my homemade CNC machine. The wheels are kept from sliding off the axle by split pins, one just outside each wheel. And then the axle also has carriers for the sprocket and the brake disc. I originally mounted both of these by making an M6 tapped cross-drilled hole in the axle, and making a hub with a 6mm cross-drilled hole through it, and then bolting the hub to the axle. This provides both axial location and torque transmission so I thought it was a simple and effective solution. You can see the head of the bolt fixing the sprocket carrier to the axle in this pic: Unfortunately fixing a hub the axle with a single bolt through a hole is not adequate because the shear force is very large. Eventually the bolt holding the sprocket on snapped. I replaced it with a new bolt and it snapped again, so then I welded the carrier to the axle. It hasn't snapped yet. Countershaft Originally I thought it would work if the motor drove the rear axle with just a chain and sprockets, but I had missed out a factor of Pi in my calculation. Having the motor drive the rear axle requires about a 30:1 reduction, which is far too extreme, would require a rear sprocket with about 300 teeth. so I added a countershaft to gain back the factor of ~3. You can see the countershaft in this pic: It is supported by a couple of small pillow block bearings on a big piece of steel box section. The shaft is simply an M12 bolt. The large sprocket is bolted to a big piece of aluminium, which is keyed to the bolt with a hexagon machined into the centre, which the bolt head is hammered into. And the small sprocket has a couple of flats on it, rather like the rear wheels, and I filed matching flats onto the threads at the end of the bolt. The motor controller that I got doesn't have a way to reverse the motor, so I implemented reverse by putting an "on-off-on" DPDT switch in the wires that go to the motor, so that in one position positive and negative connect to the motor one way, in the middle position it's disconnected, and in the third position the polarity is reversed. This works fine but you need to make sure your switch can handle the current. In my case it's not too hard because 350W at 36V is only 10 amps. You can see the switch sticking up from underneath the chassis here: (It has a black rubbery cover). I later added a lever so that it is easier to switch: The lever has no actual bearings, it just rides in holes drilled in the wood. This is more than adequate for the kind of speeds and loads that a gear lever experiences, which are basically zero. The holes just need to constrain its location. A bonus is that the natural friction in the holes prevents the lever from rattling around. I did add a gate to indicate the selection, and constrain the movement to prevent damaging the switch: The text is done with multicolour printing on the Bambu X1 Carbon. I think the brake is from a mini moto. It doesn't work very well and I haven't done a very good job of fitting it. You can pretty much see how it works in this pic: The pedal on the left-hand side (right-hand side in pic) pulls on the cable, which then pulls on the lever on the caliper, which presses the pads against the disc. Like the gear lever, the shaft is not on any sort of bearing, it just pivots in holes drilled in the wood. I think this is also fine for the brake, because it doesn't get much use, although the force on the brake pedal is much higher than on the gear lever. If the pivots do get worn out then they can easily be drilled out and bushed. I put off making the bonnet for a good while because I originally wanted to do something like a Ferguson TE20 bonnet: But I couldn't work out how to do all the curves. My best plan was to break up the design into large flat surfaces and small curved surfaces, and make the large flat parts out of plywood and 3d print the small curved parts and somehow join them together and body-fill over the crimes. But then Lucy acquired this toy tractor: And I saw that there is no need for the complex compound curves. Just a single curve will do. So I tried to form the curved part with "kerf bending", but: It instantly snapped instead of bending. I think I had the grain in the outer layer of plywood running in the wrong direction. It might have bent nicely if it was the other way. In for a penny, in for a pound, I carried on: And actually that was starting to look like I might get away with it. So I filled the gaps with glue to make it hold its shape. And after a few rounds of body-filling and sanding, I was actually really pleased with the result. Throttle conditioner The throttle response is very dissatisfying. It starts off from a standstill with quite a violent kick and then immediately tapers off into having hardly any power at all. So the plan was to make an Arduino project that would take the throttle position as input and output a "conditioned" throttle position as output, which would ramp up gradually as you initially apply the throttle. The throttle conditioner is in the yellow box here: While it did work , it also somehow prevented the throttle from ever reaching 100%. The throttle position is transmitted as an analogue signal, and I think the analogue output of the Arduino topped out at a lower voltage than 100% throttle. I didn't care to fix it, and I realised that this was an unnecessary complexity, so I just removed the electronics. I even had a magnet and sensor to detect when it was changed between forwards and reverse so that it would instantly cut the throttle when you change direction to avoid damage. But this is not the way. A machine should obey the will of its operator, not its constructor, and it is incumbent on the operator not to operate in a way that damages the machine. I despise painting. It is one of those jobs that takes way longer than it feels like it ought to. Step 1: disassemble the completed tractor. Step 2: brush paint white "knot-block" primer onto the chassis. Step 3: spray grey primer on everything. Step 4: draw the rest of the owl. It's a long time since I did a lot of welding, and my welds on this tractor are rather poor. I have experimented with the welder today and discovered that my prior mental model about how the welder works was totally wrong. I had thought that turning up the voltage would make it "hotter", and turning up the wire speed would make it "build up more material". As if it's a 3d printer extruder and voltage sets temperature and wire speed sets extrusion feed rate. But that's not how it works at all! In fact turning up the wire speed makes it hotter, and turning down the voltage makes it build up more material. I don't really understand the physics of why that is the case, but at least I know how to control the machine now.

Hardware Electronics

Jeff Geerling 1 months ago

Raspberry Pi Pico Mini Rack GPS Clock

I wanted to have the most accurate timepiece possible mounted in my mini rack. Therefore I built this: This is a GPS-based clock running on a Raspberry Pi Pico in a custom 1U 10" rack faceplate. The clock displays time based on a GPS input, and will not display time until a GPS timing lock has been acquired. For full details on designing and building this clock, see: When you turn on the Pico, the display reads Upon 3D fix, you get a time on the clock, and the colon starts blinking If the 3D fix is lost, the colon goes solid When the 3D fix is regained, the colon starts blinking again

Electronics Hardware

iDiallo 1 months ago

Boredom is the Gatekeeper

That first Monday of my holiday break, I made a promise to myself. No work emails, no side projects, not even glancing at my blog. This time was for family, for Netflix queues, for rereading dog-eared novels. One thing I was really looking forward to was learning something new, a new skill. Not for utility, but purely for curiosity. I wanted to learn about batteries. They power our world, yet they're a complete mystery to me. I only vaguely remember what I learned in high school decades ago. This would be the perfect subject for me. I went straight to a website I had bookmarked years ago in a fit of intellectual ambition: BatteryUniversity.com. I started with the chemistry of lead acid batteries. I was ready to be enlightened. Twenty minutes later, I was three paragraphs in, my mind adrift. The text was dense, packed with terms like "lead-antimony" and "acid-starved." My finger twitched. Then I read this: the sealed lead acid battery is designed with a low over-voltage potential to prohibit the battery from reaching its gas-generating potential during charge. I thought, wouldn't this be easier to understand as a YouTube video? A nice animation? I clicked away. It seemed like I had just met the gatekeeper, and it had turned me away. I was bored. We talk about boredom as if it's the absence of stimulation. Having nothing to do. But in our hyperconnected world, where information is constantly flowing and distractions are a finger tap away, true emptiness is rare. Modern boredom isn't having nothing to do. I had plenty of material to go over. Instead, it's the friction of deep focus. It's the resistance you feel when you move from consuming information to building those neural connections in your brain. Learning feels slow and hard, and it is ungratifying compared to dopamine-induced YouTube videos. Have you ever watched a pretty good video on YouTube and learned nothing from it? This reaction to learning the hard way, masquerading as boredom, is the gatekeeper. And almost every important skill in life lives on the other side of that gate. When I started working for an AI startup, I was fascinated by what we were able to accomplish with a team of just two engineers. It looked like magic to me at first. You feed the AI some customer's message, and it tells you exactly what this person needs. So, to be an effective employee, I decided to learn profoundly about the subject. Moving from just a consumer of an API to a model creator made the process look un-magical. It started with spreadsheets where we cleaned data. There was a loss function that stubbornly refused to budge for hours. There was staring at a single Python error that said the tensor dimensions don't align. The boring part was the meticulous engineering upon which the magic is built. I find it fascinating now, but it was frustrating at the time, and I had to force myself to learn it. Like most developers, video games inspired me to become a programmer. I wanted to code my own game from scratch. I remember playing Devil May Cry and thinking about how I would program those boss battles. But when I sat with a keyboard and the cursor on my terminal flashed before me, I struggled to move a gray box on the screen using SDL. For some reason, when I pressed arrow keys, the box jittered instead of following a straight line. I would spend the whole day reading OpenGL and SDL documentation only to fix a single bug. Boredom was going through all this documentation, painfully, only to make small incremental progress. When you start a business, the gatekeeper shows its face. It stares back at you when you open that blank document and write a single line of text in it: My idea. For indie developers, it's the feeling you get when you build the entire application and feel compelled to start over rather than ship what you've built. This boredom is the feeling of creation from nothing, which is always harder than passive consumption. We've conflated "interesting" with "easy to consume." The most interesting things in the world, like building software, writing a book, mastering a craft, understanding a concept, are never easy to produce. Their initial stages are pure effort. Gamification tries to trick us past the gatekeeper with points and badges, but that's just putting a costume on it. The real work remains. There is no way around it. You can't eliminate that feeling. Instead, you have to recognize it for what it is and push through. When you feel that itchy tug toward a distracting tab, that's the gatekeeper shaking its keys. It's telling you that what you're doing is really hard, and it would be easier to just passively consume it. You might even enjoy the process without ever learning anything. Instead, whenever you feel it, set a timer for 25 minutes. Agree to wrestle with the battery chemistry, the Python error, or the empty page. Just for that short time span. There is no dopamine hit waiting on the other side of boredom like you get from passive consumption. Instead, the focus, the struggle, the sustained attention, that's the process of learning. The gatekeeper ensures only those willing to engage in the hard, quiet work of thinking get to the good stuff. I did not become a battery expert over the holidays. But at least I learned to recognize the gatekeeper's face. Now, when I feel that familiar, restless boredom descend as I'm trying to learn something hard, I smile a little. I know I'm at the threshold. And instead of turning back, I take a deep breath, set my timer to 25 minutes, and I power through the gate.

Career Electronics Python Science

Jason Fried 1 months ago

The big regression

My folks are in town visiting us for a couple months so we rented them a house nearby. It’s new construction. No one has lived in it yet. It’s amped up with state of the art systems. You know, the ones with touchscreens of various sizes, IoT appliances, and interfaces that try too hard. And it’s terrible. What a regression. The lights are powered by Control4. And require a demo to understand how to use the switches, understand which ones control what, and to be sure not to hit THAT ONE because it’ll turn off all the lights in the house when you didn’t mean to. Worse. The TV is the latest Samsung which has a baffling UI just to watch CNN. My parents aren’t idiots, but definitely feel like they’re missing something obvious. They aren’t — TVs have simply gotten worse. You don’t turn them on anymore, you boot them up. The Miele dishwasher is hidden flush with the counters. That part is fine, but here’s what isn’t: It wouldn’t even operate the first time without connecting it with an app. This meant another call to the house manager to have them install an app they didn’t know they needed either. An app to clean some peanut butter off a plate? For serious? Worse. Thermostats... Nest would have been an upgrade, but these other propriety ones from some other company trying to be nest-like are baffling. Round touchscreens that take you into a dark labyrinth of options just to be sure it’s set at 68. Or is it 68 now? Or is that what we want it at, but it’s at 72? Wait... What? Which number is this? Worse. The alarm system is essentially a 10” iPad bolted to the wall that has the fucking weather forecast on it. And it’s bright! I’m sure there’s a way to turn that off, but then the screen would be so barren that it would be filled with the news instead. Why can’t the alarm panel just be an alarm panel? Worse. And the lag. Lag everywhere. Everything feels a beat or two behind. Everything. Lag is the giveaway that the system is working too hard for too little. Real-time must be the hardest problem. Now look... I’m no luddite. But this experience is close to conversion therapy. Tech can make things better, but I simply can’t see in these cases. I’ve heard the pitches too — you can set up scenes and one button can change EVERYTHING. Not buying it. It actually feels primitive, like we haven’t figured out how to make things easy yet. That some breakthrough will eventually come when you can simply knock a switch up or down and it’ll all makes sense. But we haven’t evolved to that point yet. It’s really the contrast that makes it alarming. We just got back from a vacation in Montana. Rented a house there. They did have a fancy TV — seems those can’t be avoided these days — but everything else was old school and clear. Physical up/down light switches in the right places. Appliances without the internet. Buttons with depth and physically-confirmed state change rather than surfaces that don’t obviously register your choice. More traditional round rotating Honeywell thermostats that are just clear and obvious. No tours, no instructions, no questions, no fearing you’re going to do something wrong, no wondering how something works. Useful and universally clear. That’s human that’s modern. -Jason

Hardware Design Electronics

Alex White's Blog 2 months ago

What to do with a VIC-20?

A family member was nice enough to get me a Commodore VIC-20 for Christmas! I grew up writing BASIC on an Atari 400 (despite being born 12 years after the release), but have always want to get my hands on a Commodore. The system needs a bit of work before I can use it though. First thing is a power supply, which shockingly seem to be $80+. I also need a video cable, but I think my Sega Genesis one will work (it fits at least). The "0" key is missing on the keyboard, so I think I'll need a new stem and keycap. I should probably buy a recap kit as well. Finally, I'll need something to load up software. Kung-Fu Flash or SD2IEC seem like good choices. Eventually I'd also like to get it online and connect to a BBS, but one step at a time! I'd love to find a way to write a blog post from it as well! For the Commodore enthuaists out there, let me know any hardware/software suggestions or thoughts on what I can do once I get the system up and running!

Gaming Hardware Electronics

Stavros' Stuff 2 months ago

I made another little bedside clock

The other day I saw a video by someone who bought a $16 electronic clock , and it looked interesting, because that little clock had been taunting me for months by showing up constantly in my AliExpress recommendations. I held off on buying it because what am I going to do with yet another clock , but the video said that it has an ESP8266 inside, and that, with a little soldering and programming, you could run ESPhome on it! Obviously, I didn’t need any more convincing, though I remembered this clock being listed for $6 for a while, and balked at the $16 the video mentioned. I ordered a different listing, which I found for $12 , hoping it would be the same as the one from the video. Fairly serendipitously for this purchase, the last bedside clock I made was showing its age a bit. Mainly, the dimmest setting on its screen was bright enough to be annoying when I’m in bed, and the screen has been burned-in quite a bit. A new monochrome OLED screen is an easy fix, but I’d prefer a color one (especially if it can be dimmed more), so hopefully I’d be able to replace the Do Not Be Alarmed clock with this new one. The new clock arrived promptly, and I got to work. The first thing I did was what any good engineer would do, I eschewed the company of my friends and shut myself in a room where I could work on my clock in peace. The second thing I did was to open the clock up, as the video mentioned, in no uncertain terms , that I would need to solder some headers if I were to ever program this clock. Imagine my surprise and dismay when, upon opening up the device, I saw no headers or any accessible points to connect anything to program it with! It turned out that what I had ordered wasn’t the same as the one in the video, after all. I wasn’t too sad about it, as I’ve programmed ESP8266 modules often by just touching the pins to the microcontroller board, and the clock has an ESP-12F package soldered on it, so the pins are large enough to connect things to, so I got ready for the agony of trying to hold five wires firmly to the board while I press the Enter key on the keyboard with my nose. At this point I was obviously cursing myself for trying to save $4 and not getting the “good” version, but it was what it was. While examining the (very simple) board, though, I flipped it over and saw what looked like a USB-TTL chip. That chip turned out to be a USB-TTL chip indeed, which took me by surprise, because it meant I didn’t even have to open the thing up! Sure enough, connecting the USB-C port to the computer showed the clock as a USB device, and flashing ESPhome worked perfectly. Next step: The configuration. I used the configuration from the video as a starting point, as it already contained the pinout for the screen, the screen type and dimensions, and various other niceties. The original configuration used Home Assistant, which I don’t use, so I took those things out. I’m terrible at any sort of visual design, so I can’t really say that I designed things with any intent, I mostly stumbled onto a design that didn’t seem terrible, and used that. I went through a few iterations, with the time first being centered and the date below it, then with the time being shown diagonally (as in the photo on the right), and finally copying the face of my Xiaomi watch and arriving at the final design. Usually I’ll open Inkscape and try to mock up something to see how the colors, layout, separators, and other visual elements fit together, but here I didn’t really do any of that, and just iterated on the display directly. It took a bit of positioning elements around, but I think the end result is pretty good. One serendipitous thing that I did was add a synthwavy-ground-grid type of thing, which gave the face a really nice touch. I initially added it as somewhat of a test, but I liked it so much I ended up keeping it in the final version. The time and date were very easy to add. ESPhome supports NTP natively, so getting the correct time over the network was just a matter of adding the appropriate NTP servers in a small stanza. This way, the time keeps updating with daylight savings time as well, following the timezone properly. This is actually a lot of work to do manually, as I found out when I made the Do Not Be Alarmed clock, and the fact that ESPhome does it for me is fantastic and saves a ton of work. It basically just worked. The last thing to add was to show various sensor values that are relevant to a bedside clock. My house is instrumented to use Zigbee (with Zigbee2MQTT), and some WiFi sensors that publish to MQTT on specific topics. ESPhome supports MQTT natively, and it can subscribe to topics, listen for updates, and update the screen whenever a topic gets published to. Usually, when I wake up, I want to know what time it is, what date, what the temperature outside is, in case I need to go out, and maybe what the humidity inside the flat is. I use Zigbee Sonoff or Aqara temperature/humidity sensors, so I wanted the values read from those. I also have a makeshift CO2 sensor in the bedroom (I made that using an ESP8266 with ESPhome and an SCD41 CO2 sensor), and I wanted to see the CO2 value so I know whether I should open a door a bit wider when it gets too high. These were the values I mainly wanted to display, so I added subscriptions in the MQTT integration to these sensors’ topics, and instructed ESPhome to parse the values they sent. Then, I positioned the elements that I wanted to show the values around the screen. At this point, there was a small issue: When the clock is restarted (which is, admittedly, rarely), the sensor values show 0, or NA, until the sensor wakes up and sends a reading, which might happen every ten minutes or so. I wanted the clock to show the last value quickly, so I enabled “retain message” in the Zigbee2MQTT options for the sensors I was interested in. “Retain” is an MQTT flag that tells the server to remember the latest message in that specific topic, and send it to you when you subscribe, no matter how long ago it was actually sent. This fixed the issue, and now the clock shows the last values on bootup, which is perfect. And now we get to the most important part of the whole project: The dimming! This clock is, indeed, much better at dimming. You can dim it very very low before turning the backlight off altogether, but it does get hard to read at very low brightnesses. I ended up using a brightness of about 6%, and a max brightness of 60%, and it’s perfect. The way min/max works is that the clock starts dimming from 60% to 6% for about an hour before the time when I usually go to bed. Then, it stays dim throughout the entire night, and starts brightening again around the time I wake up, and takes an hour to go back to 60% brightness. This way, the clock is dim throughout the night when I’m asleep, but bright in the day, when I might need to look at it in well-lit conditions. This works really well and is a massive improvement on my last clock, and the nice, colorful screen doesn’t hurt, either. With that, the clock was complete! This was a very simple build, and it only took an hour or two, but it was lots of fun and I absolutely love the final result. I also really like the fact that I get a lot of use out of something like this. I look at my bedside clock a lot, and having a better clock is a massive quality of life upgrade. I’ve been looking for a better clock for ages, but never found one that ticked all the boxes, until this one came along. I heavily recommend buying one, you can use my config to program it with, and customize it to your liking: https://github.com/skorokithakis/esphome-configs There’s also a version with an ESP32, which is much more powerful, but I don’t know if the pinouts have been figured out yet, so I don’t know how easy it would be to program. However, if you do get one of these clocks, I’ll be looking forward to anything you make with it, if you want to share! As always, if you have any questions or feedback, please let me know! You can find me on X or BlueSky , or email me directly.

Hardware Electronics

Alex White's Blog 2 months ago

Palm Tungsten C

Mail day and an early birthday present to myself! My new-to-me Tungsten C arrived today, and let me say, it is an absolute joy to use! The C has a smaller screen than my T3, WiFi instead of Bluetooth and is a bit heavier. The build quality is solid, par for the course when it comes to Tungsten devices. The CPU is similar to the T3, but seems noticeably faster (especially in Acid Freecell). Without a doubt, the keyboard is the killer feature. I had forgotten how much I prefer a chicklet, physical keyboard to poking at a touchscreen. It's fast, easy to hit keys, and has a great clicky feeling to it. On the Wi-Fi front, I have yet to successfully connect to a network. My guess is my UniFi APs and Pixel Phone Hotspot use newer bands than the C supports. I might have an older router somewhere to give a shot later on. All in all, this is a great little device that will replace my T3 as my pocket carry. The keyboard just makes it such a productivity beast, even when compared to a modern cell phone! This post was, of course, written on my Tungsten C. Update on Wi-Fi Seems my Wi-Fi chip might be shot. Trying to do a system update errors saying that the radio ROM is corrupt. I have a new battery coming in the mail, so I'll see if there's anything obvious that needs soldering while I'm in there.

Hardware Electronics

Maurycy 2 months ago

More uranium ore:

In many places, natural minerals aren’t even regulated as radioactive material (10 CFR § 40.13 b) … but you should check your local laws before collecting any. Radiacode 102: 180 CPS [4 uSv/h]. Ludlum 44-9: 20 kCPM. Carnonite from the Mc Cormic mine near Mi Vida in Utah, USA. It’s quite dusty, I’ll have to put this one in a display case. The biggest hazard isn’t the radiation, but uranium’s chemical toxicity. (similar to lead) Radiacode 102: 1700 CPS [40 uSv/h]. Ludlum 44-9: 70 kCPM. Uraninite in sandstone from around the Mi Vida mine in Utah, USA. This one is quite spicy, the Radiacode measures 50 CPS [1 uSv/h] at 15 cm distance. My prospecting detector detects it from a meter away. Based on gamma dose constants, I estimate a uranium content of 10-20 grams, but take that number with a (large) grain of salt. Radiacode 102: 2 CPS [0.1 uSv/h]. Ludlum 44-9: 350 CPM. Unknown U(IV) mineral (perhaps natrozippeite?) from Yellow Cat (Parco claims) Unlike the Carnonite, these glow the classic “nuclear waste” green under 365 nm: For the record: spent fuel doesn’t glow this color outside of Hollywood. However, many uranium minerals and uranium containing glass will glow green under ultraviolet light. Radiacode 102: background. Ludlum 44-9: background. Jasper from Yellow Cat . Not radioactive, but it looks cool: it’s what most people go to the area for. Radiacode 102: background. Ludlum 44-9: background. Petrified wood from near the McCormic mines. (close to Mi Vida ) Not significantly radioactive despite being close to the uranium deposit.

Science Security Electronics

Jeff Geerling 2 months ago

CM0 - a new Raspberry Pi you can't buy

This little postage stamp is actually a full Raspberry Pi Zero 2, complete with eMMC storage and WiFi. But you can't get one. Well, not unless you buy the CM0NANO development board from EDAtec , or you live in China. This little guy doesn't have an HDMI port, Ethernet, or even USB. It's a special version of the 'Compute Module' line of boards. Little Raspberry Pi 'System on Modules' (SoMs), they're called. Compute Modules are entire Linux computers about the size of a regular desktop CPU that you 'plug in' to another board, to give it life.

Electronics Hardware Open Source

Stratechery 2 months ago

Trump Allows H200 Sales to China, The Sliding Scale, A Good Decision

The Trump administration has effectively unwound the Biden era chip controls by selling the H200 to China; I agree with the decision, which is a return to longstanding U.S. policy.

Business Electronics

HeyDingus 2 months ago

I’m not a ring guy, but…

I’m not a ring guy. My parents had to cajole me into getting a class ring back in high school, telling me that it would be something that I would later regret if I didn’t get one. So I got one, tried wearing it, and ended up hating the feeling of it always spinning ’ round my finger. And then I lost it in my bowling ball bag for like a year. I’ve got no idea where it is today. My next ring was my wedding band. Again, following customary traditions, I spent so much of my savings on an engagement and wedding ring combo for my wife. But for my own ring, I wasn’t particular. I looked around online for design ideas, liked the look of a tungsten one, found one for like $15 on Amazon, and clicked ‘ Buy Now’. It still looks good as new over seven years later. And while I liked the feel of it better than my old class ring since it was symmetrical and didn’t tend to fall to one side of my finger or the other, I still prefer my fingers unornamented. In fact, since becoming a mountain guide, I’ve worn my wedding band on a piece of cord around my neck, lest it get wedged in a rock somewhere while I’m climbing, which could be disastrous. I’d like to get a tattooed ring on my finger someday. 1 Likewise, I’ve tended to be skeptical of the fitness rings, such as the Oura , partly because I figure I’d dislike wearing it at least as much as any other ring. But also because my Apple Watch already handles all my fitness tracking, and I wouldn’t want another thing to remember to charge. All that being said, I’m as surprised as anyone that the Index 01 , Pebble’s latest gadget, caught my interest. It’s a ring, but instead of packing in more features than its competition, the Index is designed to do less . Its primary role is to be an ever-present way to record short notes-to-self. It’s got a tiny LED and a little microphone that’s activated by pressing a physical button. That’s it. Eric Migicovsky, Pebble’s founder, is selling the Index as “ external memory for your brain”. It doesn’t have any fitness tracking sensors. It doesn’t record everything around you, 24/7, like other AI gadgets , to make a perfect transcript of your life. It’s basically a dedicated personal note taker, and that’s what makes it so interesting to me. In fact, I’ve been trying to solve this ‘ take a quick note’ problem on my own for years. My brain comes up with its best ideas when I’m out for a hike, but that’s also when I least want to pull out my phone to type it out. So, I rigged up a solution with Apple Shortcuts to trigger voice-to-text with my iPhone’s Action button so that I can easily save my ideas and to-dos to Drafts without breaking stride. But it’s an imperfect solution as I look a little goofy in front of my clients when I mutter into my phone in the backcountry. Plus, I have to have my phone with me, and the audio isn’t saved, just the transcript. The Index remedies a lot of that rigmarole by virtue of being a dedicated device that’s always with you, that saves the audio recording, and that’s less intrusive and distracting than pulling out a smartphone. The physical button. You have to hold it down to make a recording. No wondering if it’s working. Migicovsky insists it has a great click-feel, and I’m inclined to believe him. It’s designed to be worn on your index finger, putting the button always in reach of your thumb to start a recording. That’s so smart, as it means it can be used discreetly with one hand. My Apple Watch often needs to be operated with the other hand, and its raise-to-speak to Siri feature is somewhat unreliable. Adding the button was a great idea. You can’t charge it. This one’s a bit controversial, I know. Just read the comments on the announcement video — it’s basically the only thing people are talking about. The non-replaceable battery is a bummer, but I get it. I’d want a ring to be as unobtrusive as possible, and leaving out the charging bits and accessible battery cuts down on a lot of bulk. It’s definitely more svelte than an Oura. Furthermore, I have enough gadgets that I need to remember to charge every day. If it can just stay on my finger, it has a way higher chance of becoming an ingrained workflow. While I don’t want to contribute to e-waste, Pebble says they’ll recycle it when the battery dies, supposedly in two or so years with typical use. The price. If this thing cost $300+, like most smart rings , I certainly wouldn’t be psyched to replace it every two years. But at $99 ($75 for pre-orders), I think they priced it well to be a reasonable curiosity purchase. And it’s a one-time payment — there’s no ongoing subscription cost! Additional actions. While its primary purpose — and my main interest in it — rests with its always-ready note-taking, it sounds like the Index can do a little processing and take action on some commands. From the announcement post : Actions: While the primary task is remembering things for you, you can also ask it to do things like ‘ Send a Beeper message to my wife - running late’ or answer simple questions that could be answered by searching the web. You can configure button clicks to control your music - I love using this to play/pause or skip tracks. You can also configure where to save your notes and reminders (I have it set to add to Notion). Customizable and hackable: Configure single/double button clicks to control whatever you want (take a photo, turn on lights, Tasker, etc). Add your own voice actions via MCP . Or route the audio recordings directly to your own app or server! Supposedly, you’ll be able to hook it up to MCP to do more AI stuff with the recordings. I don’t know enough about MCP , so that’s not of huge interest to me. But if it can send quick messages, make reminders and calendar events, and control audio playback — and do so reliably — that’d be pretty great. Works offline. It doesn’t have or need an internet connection to work. Transferring the audio file goes directly to your phone, and the transcription is done there, on-device. If you set those additional actions that need the internet, that’s another story, but the Index will serve its primary purpose offline, without sending your (potentially very personal) recordings to anyone’s servers. Less-than-stellar water-resistance. Pebble’s billed the Index as something that you never have to take off, but then notes it’s water-resistant only to 1 meter. They note, “ You can wash your hands, do dishes, and shower with it on, but we don’t recommend swimming with it.” That’s not a deal-breaker, but I’ve grown so used to not worrying about swimming with my watch that I’d be a little grumpy about having to remember to take off my ring before jumping in a pool or lake. Short answer, yes. I’m intrigued enough that I placed a pre-order this morning. But I’m still a little iffy on whether I’ll keep it. As I mentioned, I wear my wedding band as a necklace so that it doesn’t put my finger at risk when I’m climbing. That would still be a factor with the Index. But I’m willing to give it a shot. My wife insists that I put my wedding ring back on my finger for date night, or culturally significant events like weddings and such. I don’t mind. ↩︎ HeyDingus is a blog by Jarrod Blundy about technology, the great outdoors, and other musings. If you like what you see — the blog posts , shortcuts , wallpapers , scripts , or anything — please consider leaving a tip , checking out my store , or just sharing my work. Your support is much appreciated! I’m always happy to hear from you on social , or by good ol' email . Actions: While the primary task is remembering things for you, you can also ask it to do things like ‘ Send a Beeper message to my wife - running late’ or answer simple questions that could be answered by searching the web. You can configure button clicks to control your music - I love using this to play/pause or skip tracks. You can also configure where to save your notes and reminders (I have it set to add to Notion). Customizable and hackable: Configure single/double button clicks to control whatever you want (take a photo, turn on lights, Tasker, etc). Add your own voice actions via MCP . Or route the audio recordings directly to your own app or server! My wife insists that I put my wedding ring back on my finger for date night, or culturally significant events like weddings and such. I don’t mind. ↩︎

Electronics Hardware Culture

Jeff Geerling 2 months ago

The DC-ROMA II is the fastest RISC-V laptop and is odd

Inside this Framework 13 laptop is a special mainboard developed by DeepComputing in collaboration with Framework. It has an 8-core RISC-V processor, the ESWIN 7702X—not your typical AMD, Intel, or even Arm SoC. The full laptop version I tested costs $1119 and gets you about the performance of a Raspberry Pi. A Pi 4—the one that came out in 2019.

Electronics Hardware