A PDA From An ESP32

January 18, 2025 by 13 Comments

The ESP32 series of microcontrollers have been with us for quite a few years now and appeared in both Tensilica and RISC-V variants, both of which deliver an inexpensive and powerful device. It’s thus shown up in quite a few handheld computers, whether they be conference badges or standalone devices, and this is definitely a field in which these chips have more to give. We’re pleased then to see this e-ink PDA from [ashtf8], which we think raises the bar on this type of device.

At its heart is an ESP32-S3, on the back side of a QWERTY keyboard PCB, and for a display it has an e-ink screen. To get over the annoying e-ink refresh when typing text it uses a hybrid of e-ink and OLED, with a small OLED holding the current line which can be periodically sent to the e-ink. Perhaps the nicest thing about the hardware though is the clear resin printed clamshell case, and a hand-cast silicone membrane for the keyboard. That has always been a part considered difficult to produce, and here he is making one from scratch. Take a look at the video below the break.

Software-wise it has a range of apps with more promised, but even as it stands it looks useful enough to work with. If that’s not enough, then perhaps an ESP32 operating system would help.

Continue reading “A PDA From An ESP32” →

A Field Expedient Welder Only MacGyver Could Love

January 17, 2025 by 46 Comments

If you needed to weld something in a pinch, what’s the minimum complement of equipment you could get away with? In [Professor Bardal]’s case, it’s a couple of motorcycle batteries and a roll of flux-core wire, and not much else.

We suspect this one is going to elicit quite a few comments, not least by the welding fans who no doubt will be triggered by just about everything in the video below, especially by characterizing this as MIG welding; it’s FCAW, or flux-core arc welding. But it bears some superficial similarities to MIG, at least insofar as there’s a consumable wire electrode through which a high-current DC supply flows, creating enough heat to melt it and the base metal. In this case, the current is provided by a pair of 12-volt motorcycle batteries hooked together in series. There’s also a torch of sorts — a short length of copper capillary tubing with a 1-mm inside diameter clamped in the jaws of a stick welder stinger, or a pair of locking pliers if you’re really in a pinch. The torch is connected to the negative terminal on the battery with a jumper cable, and the positive terminal is connected to the workpiece.

To create the weld, a piece of 0.8-mm flux-core welding wire is threaded through the capillary and into the joint, and fed by hand as it’s consumed. It’s awkward and awful, but it works. Of course, there’s no control over amperage as there would be with a legit welding machine, which would make it hard to adapt this method to different materials. Weld quality appears poor, too. But we suspect that if you were in a position to need a welder like this, you wouldn’t really care about any of that.

Fabricobbled welding rigs seem to be [Professor Bardal]’s thing — witness this much more professional MIG welder, complete with a baking soda and vinegar shielding gas generator.

Continue reading “A Field Expedient Welder Only MacGyver Could Love” →

No Crystal Earpiece? No Problem!

January 17, 2025 by 11 Comments

A staple of starting off in electronics ion years past was the crystal set radio, an extremely simple AM radio receiver with little more than a tuned circuit and a point contact diode as its components. Point contact diodes have become difficult to find but can be replaced with a cats whisker type detector, but what about listening to the resulting audio? These circuits require a very high impedance headphone, which was often supplied by a piezoelectric crystal earpiece. [Tsbrownie] takes a moment to build a replacement for this increasingly hard to find part.

It shouldn’t have come as a surprise, but we were still slightly taken aback to discover that inside these earpieces lies the ubiquitous piezoelectric buzzer element. Thus given a 3D-printed shell to replace the one on the original, it’s a relatively simple task to twist up a set of wires and solder them on. The result is given a test, and found to perform just as well as the real thing, in fact a little louder.

In one sense this is such a simple job, but in another it opens up something non-obvious for anyone who needs a high impedance earpiece. The days of the crystal radios and rudimentary transistor hearing aids these parts were once the main target for may both have passed, but just in case there’s any need for one elsewhere, now we can fill it. Take a look at the video, below the break.

Fancy trying a crystal radio? We’ve got you covered.

Continue reading “No Crystal Earpiece? No Problem!” →

Trinteract, a small space mouse, operating in Blender.

Trinteract Mini Space Mouse Does It In 3D

January 17, 2025 by 17 Comments

We’re not sure how we managed to miss this one, but better late than never, right? This is Trinteract, a 3-DOF input device that’s both open-source and Arduino compatible. There’s even a neat 3D-printed clip to add it to the side of your laptop.

Imagine navigating 2D and 3D environments, or flying around in Minecraft with ease. [Görkem]’s custom PCB features a Hall effect sensor which picks up readings from the magnet embedded in the bottom of the joystick. You can use any magnetic object as input. In the video below the break, [Görkem] shows a 3D-printed sphere with a disc magnet trapped inside as an alternative. The super-neat part is that the thing moves around entirely on flexures. You know how much we love flexures around here.

[Görkem] has written up a fantastic guide for those who must have one of their own. As a bonus, the guide details the background and thought process behind the design, which we love to see.

Don’t like magnets? This space mouse uses an accelerometer and a spring.

Continue reading “Trinteract Mini Space Mouse Does It In 3D” →

Android Head Unit Gets Volume Knob Upgrade

January 17, 2025 by 21 Comments

Touch screen head units are pretty much the norm these days. Many compromise with annoying on-screen volume controls or tiny buttons. If you find yourself with such a unit, you  might like to hack in a real volume knob. [Daniel Ross] shows us how to do just that.

The build uses an ATMega328 as the heart of the operation, though [Daniel] notes an Arduino Uno or Mini would have done just fine. It’s set up with a 74HC14 hex Schmitt trigger, and a CD4066 quad bilateral switch on a custom PCB. As for the volume knob itself, it’s not a real analog pot, instead it’s using a rotary encoder with a center push button. The way it works is that the Arduino reads the encoder, and figures out whether you’re trying to turn the volume up or down based on the direction you’re turning it. It then sends commands to the CD4066 to switch resistors in and out of circuit with lines going to the stereo to emulate the action of volume buttons on the steering wheel.

[Daniel’s] guide explains how everything works in greater detail, and how you can calibrate your head unit to accept these signals while preserving the function of your actual steering wheel volume buttons. Then you just have to find a neat way to integrate the knob into your existing dashboard.

We don’t see as many car stereo hacks in this era when infotainment systems rule all, but we’ve seen some great stuff from older vehicles over the years. Video after the break.

Continue reading “Android Head Unit Gets Volume Knob Upgrade” →

New Bambu Lab Firmware Update Adds Mandatory Authorization Control System

January 17, 2025 by 102 Comments

As per a recent Bambu Lab blog post, its FDM printers in the X1 series will soon receive a firmware update that adds mandatory authentication for certain operations, starting with the firmware update on January 23rd for the aforementioned FDM printers. These operations include performing firmware upgrades, initiating a print job (LAN or cloud), remote video access and adjusting parameters on the printer. Using the printer directly and starting prints from an SD card are not affected.

As reasoning for this new feature Bambu Lab points to recent exploits that gave strangers access to people’s printers, though cheekily linking to an article on an Anycubic printer exploit. While admittedly a concern, this mostly affects internet-exposed printers, such as those that are tied into a ‘cloud’ account. Even so, LAN-based printing also falls under this new mandatory authentication system, with Bambu Lab offering a new tool called Bambu Connect for those who insist on using non-Bambu Lab branded software like OrcaSlicer. This allows for exported G-code files to be sent to a (property authenticated) Bambu Lab printer.

For those who do not wish to use this feature, not upgrading the firmware is currently the only recourse. Although this firmware update is only for X1-series printers, Bambu Lab promised that it’ll arrive for their other printers too in due time. While Bambu Lab printer owners consider installing the alternative X1 Plus firmware, the peanut gallery can discuss the potential security issues (or lack thereof) of an open Fluidd or similar UI on their LAN-connected, Klipper-based FDM printers.

Thanks to [mip] for the tip.

Hackaday Podcast Episode 304: Glitching The RP2350, Sim Sim Sim, And A Scrunchie Clock

January 17, 2025 by 1 Comment

It’s podcast time again, and this week Dan sat down with Elliot for a look back at all the cool hacks we’ve written about. We started off talking about Hackaday Europe, which is coming up in March — seems unlikely that it’s just around the corner, but there it is. There’s also good news: the Hack Chat is back, and we started things off with a bang as Eben Upton stopped by to talk all things Pi. Separately, we talked about fault injection attacks, including how to find the hidden cup of  0xC0FFEE in an RP2350.

We saw a very cool piece of LED jewelry that does a fluid simulation, a direct conversion radio that’s all laid out in front of you, and the scrunchiest mechanical digital clock you’ll ever see. We saw blinkenlights for blinkenlights’ sake, all the ways to put threads in your prints, and how to ditch to coax and wire up your antennas with Cat 6 cable. Plus, it’s an Al Williams twofer in the Can’t-Miss Articles, with a look back at life before GPS and how you can tune into digital ham radio, no radio required.

Where to Follow Hackaday Podcast

Places to follow Hackaday podcasts:

Download the zero-calorie MP3.

Continue reading “Hackaday Podcast Episode 304: Glitching The RP2350, Sim Sim Sim, And A Scrunchie Clock” →