Reverse Engineering Reveals EV Charger Has A Sense Of Security

November 16, 2022 by Dan Maloney 11 Comments

As more and more electric vehicles penetrate the market, there’s going to have to be a proportional rise in the number of charging stations that are built into parking garages, apartment complexes, and even private homes. And the more that happens, the more chargers we’re going to start seeing where security is at best an afterthought in their design.

But as this EV charger teardown and reverse engineering shows, it doesn’t necessarily have to be that way. The charger is a Zaptec Pro station that can do up to 22 kW, and the analysis was done by [Harrison Sand] and [Andreas Claesson]. These are just the kinds of chargers that will likely be widely installed over the next decade, and there’s surprisingly little to them. [Harrison] and [Andreas] found a pair of PCBs, one for the power electronics and one for the control circuits. The latter supports a number of connectivity options, like 4G, WiFi, and Bluetooth, plus some RFID and powerline communications. There are two microcontrollers, a PIC and an ARM Cortex-A7.

Despite the ARM chip, the board seemed to lack an obvious JTAG port, and while some unpopulated pads did end up having a UART line, there was no shell access possible. An on-board micro SD card slot seemed an obvious target for attack, and some of the Linux images they tried yielded at least a partial boot-up, but without knowing the specific hardware configuration on the board, that’s just shooting in the dark. That’s when the NAND flash chip was popped off the board to dump the firmware, which allowed them to extract the devicetree and build a custom bootloader to finally own root.

The article has a lot of fascinating details on the exploit and what they discovered after getting in, like the fact that even if you had the factory-set Bluetooth PIN, you wouldn’t be able to get free charging. So overall, a pretty good security setup, even if they were able to get in by dumping the firmware. This all reminds us a little of the smart meter reverse engineering our friend [Hash] has been doing, in terms of both methodology and results.

Thanks to [Thinkerer] for the tip.

Detecting Radiation For Fun And Profit

November 9, 2022 by Al Williams 19 Comments

It used to be that every well-stocked doomsday bunker had a Geiger counter. These days, you don’t have to have a big tube-based meter. You can inexpensively get a compact digital instrument to handle your radiation detection needs. [DiodeGoneWild] reviews and tears down such a unit from FNIRSI. The case looks like several other similar instruments we’ve seen lately, so presumably, someone is mass-producing these handheld meter cases. You can see the video, below. The meter reads the absolute radioactivity and can also measure cumulative exposure.

After measuring a few common radioactive items, we get to the teardown. Inside, of course, is an ordinary tube. A few screws reveal a typical rechargeable battery, a fairly simple PCB with a microcontroller and battery backup for the real-time clock. A lot of the board is involved in multiplying voltage up to the several hundred volts required for the Geiger tube.

The other side of the PCB has only buttons, a vibration motor, and, of course, the LCD. We don’t know how you might test the relative accuracy other than comparing it to a known-good meter. The bare tube was, of course, more sensitive without the plastic cover, but that could be calibrated out, too.

A Geiger counter doesn’t have to have a lot of parts. Either way, a surprising number of things will set them off.

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Look Inside This “Meditation Headband” And Integrate It Into Your Own Projects

October 23, 2022 by Donald Papp 10 Comments

Muse makes a variety of wearable devices aimed at measuring brain and body activity, and [Becky Stern] did a detailed teardown of the Muse S model, revealing what goes on inside the device.

The Muse S is a soft, sleep-friendly biofeedback wearable mounted on silver-plated fabric. Not only does [Becky] tear it down, but she provides loads of magnified images and even has it CT scanned. The headband has conductive fabric embedded into it, and the core of the device is stuffed with three separate PCBs that get pretty thoroughly scrutinized.

While the Muse S is sold mainly as a meditation aid and works with a companion app, there is, fortunately, no need to go digging around with a screwdriver and soldering iron to integrate it into other projects. The Muse S is supported by the Brainflow project which opens it up to different applications. Brainflow is a library intended to obtain, parse, and analyze EEG, EMG, ECG, and other kinds of data from biosensors.

If you think Muse and Brainflow sound familiar, that might be because of another project we featured that integrated a Muse 2 and Brainflow with Skyrim VR, creating a magic system whose effectiveness depends on the player’s state of mind. Good things happen when hardware and software are accessible to users, after all.

You can watch a video tour of the teardown in the video, embedded just under the page break.

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Condemned Precision Capacitors Find New Home, Refuse To Become Refuse

July 24, 2022 by Ryan Flowers 12 Comments

Ah, the age old tradition of Dumpster diving! Sometimes we happen to spot something that’s not quite trash, but not quite perfect, either. And when [dzseki], an EEVblog.com forum user, spotted some high-precision capacitors being 86’d at their employer’s e-waste pile, [dzseki] did what any good hacker would do: took them home, tested them, and tore them down to understand and either repair or reuse them. They explain their escapades and teardown in this EEVblog.com forum post.

High-precision capacitors with RF connectors.

If you’re not familiar with capacitors, they are really just two or more plates of metal that are separated by an insulator, and in the case of these very large capacitors, that insulator is mostly air. Aluminum plates are attached with standard bolts, and plastic insulators are used as needed. There’s also discussion of an special alloy called Invar that lends to the thermal stability of the capacitors.

[dzseki] notes that these capacitors were on their way to the round file because they were out of spec, but only by a very, very small amount. They may not be usable for the precision devices they were originally in, but it’s clear that they are still quite useful otherwise. [dzseki]

Of course, Dumpster diving for cool parts is nothing new, and we’ve covered nifty projects such as this frankenmonitor bashed together from two bin finds.

Thank you [David] for the great tip, and don’t forget to leave your own in the Tip Line.

Teardown: How Many Teddy Ruxpins Does It Take To Start A Coven?

July 21, 2022 by Kristina Panos 35 Comments

Well, I did it. I conquered my childhood fear of talking bears and brought a vintage Teddy Ruxpin animatronic stuffed bear into my home. There were and still are plenty of his brethren both young and old to choose from on the auction sites, and when I saw this particularly carefree barefoot Teddy in his Hawaiian shirt and no pants, I was almost totally disarmed. Plus, the description promised a semi-working unit with a distorted voice, and who among us could resist a specimen in such condition? Maybe the tape deck motor is going out, or it just needs a new belt. Maybe the tape itself messed up, and Teddy is fine. I had to find out.

But let me back up a bit. If you don’t know what I’m talking about, Teddy Ruxpin was a revolutionary toy that dropped in 1985. It’s a talking teddy bear that reads stories aloud, all the while moving his eyes and mouth to the sounds. Along with Teddy came special cassette tapes, corresponding story books, and outfits. I wanted one when I was a kid, but was also kind of scared of them. Since they were so expensive — about $250 inflation-adjusted for the bear and a single tape / book / outfit, plus another $15 for four D cells — I never did get one in my youth.

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Teardown: KC Bearifone Could Talk Circles Around Teddy Ruxpin

June 27, 2022 by Kristina Panos 43 Comments

At the risk of dating myself, I will tell you that grew up in the 80s — that decade of excess that was half drab and half brightly colored, depending on where you looked, and how much money you had for stuff like Memphis design. Technology seemed to move quickly in almost every aspect of life as the people of the Me decade demanded convenience, variety, and style in everything from their toilet paper (remember the colors?) to their telephones. Even though long distance cost a fortune back then, we were encouraged to ‘reach out and touch someone’.

A Healthy Fear of Bears

Looking back, it’s easy to see how all that advanced technology and excess filtered down to children. I may be biased, but the 80s were a pretty awesome time for toys, and for children’s entertainment in general. Not only were the toys mostly still well-made, even those that came in quarter machines — many of them were technologically amazing.

Take Teddy Ruxpin, which debuted in 1985. Teddy was the world’s first animatronic children’s toy, a bear that would read stories aloud from special cassette tapes, which moved his eyes and mouth along with the words. One track contained the audio, and the other controlled three servos in his face.

I remember watching the commercials and imagining Teddy suddenly switching from some boring bedtime story over to a rockin’ musical number a là the animatronic Rock-afire Explosion band at ShowBiz Pizza (a Chuck E. Cheese competitor). That’s the kind of night I wanted to be having.

The current lineup of the Rock-afire Explosion. Image via Servo Magazine

Although I went to ShowBiz a fair number of times to play Skee-Ball and stare at the Rock-afire Explosion animals and their cool set pieces, I never did have a Teddy Ruxpin. I remember being torn between wanting one and thinking they were kind of scary, which in turn made me a bit tangentially afraid of the Snuggle bear. When it came down to it, Teddy simply cost too much — $69.99 for the bear alone, and another $20 for a single cassette with storybook. And that’s 1985 dollars — according to my favorite inflation calculator, that’s $250 in today’s money for a talking bear and one lousy story.

Which brings us to KC Bearifone, an animatronic teddy bear telephone. Honestly, part of the reason I bought the Bearifone was some sort of false nostalgia for Teddy. The main reason is that I wanted to own a Teleconcepts unit of some kind, and this one seemed like the most fun to mess around with. A robot teddy bear that only does speakerphone? Yes, please.

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Becky Stern, David Cranor, And A CT Scanner Vs The Oura Ring

May 10, 2022 by Elliot Williams 7 Comments

If you wonder how it’s possible to fit a fitness tracker into a ring, well, you’re not alone. [Becky Stern] sent one off to get CT scanned, went at it with a rotary tool, and then she made a video about it with [David Cranor]. (Video embedded below.)

While it’s super cool that you can do a teardown without tearing anything down these days — thanks to the CT scan — most of the analysis is done on a cut-up version of the thing through a normal stereo microscope. Still, the ability to then flip over to a 3D CT scan of the thing is nice.

We absolutely concur with [Becky] and [David] that it’s astounding how much was fit into very little space. Somewhere along the way, [David] muses that the electrical, mechanical, and software design teams must have all worked tightly together on this project to pull it off, and it shows. All along, there’s a nice running dialog on how you know what you’re looking at when tearing at a new device, and it’s nice to look over their shoulders.

Then there’s the bit where [Becky] shows you what a lithium-ion battery pack looks like when you cut it in half. She says it was already mostly discharged, and she didn’t burst into flames. But take it easy out there! (Also, make sure you take your hot xylene out on the patio.)

X-ray machines are of course just the coolest thing when doing a teardown. We’ve seen them used from fixing multimeters to simply looking at servo motors.

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