Author: Jenny List

3248 Articles

Generating A Lost Password By Traveling Back In Time

May 31, 2024 by 5 Comments

It’s probable that some of you reading this will have been approached in the past by people who’ve lost the password to their crypto wallets. They hear that you’re involved in some kind of “hacking”, and they cling to the forlorn hope that you might just be able to recover their lost wealth. For most of us there’s little chance we can help, but in [Joe Grand]’s case he has made it something of a specialism. He’s given an account of how he and a friend recovered a particularly difficult password.

The password in question had been generated by RoboForm, a long random string that was impossible for its owner to remember. The only chance of finding it lay in discovering a flaw in RoboForm, and that seemed hopeless until the discovery of a changelog reference to improving the random number generation of the software.

The video below details some of the detective work required to find the password, first reverse engineering an old version of RoboForm to find the flaw, and then the discovery that the random seed was derived from the system time. A range of passwords could be created for a given time frame, reducing the odds of finding the password considerably. The story is not without its twists, but it ends with the wallet’s owner rather theatrically being presented with a giant fake Bitcoin check.

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CH32V003 Provides Ultra Cheap Speech Recognition

May 30, 2024 by 6 Comments

Speech recognition was once the stuff of science fiction, but it’s now possible with relatively modest hardware. Just how modest, you ask? How about a 10 cent microcontroller?

[Brian Smith] has achieved a very basic form of speech recognition on a CH32V003 RISC-V microcontroller. It may only recognize spoken digits, but that it does so at all on such a modest platform is impressive in itself.

For training purposes it enlists the help of a desktop Linux computer, however the recognition process is purely in the ten cent chip. He goes into much detail about how it achieves this on a system without floating point arithmetic, as well as the other shortcomings of such a limited platform.

We’ve become used to thinking of super-cheap chips as of limited use, but the truth is they’re surprisingly more capable than expected. We’re seeing them starting to appear as subsidiary processors on some badges, so it will be interesting to see them proliferate in more projects now their availability problems have eased. Go on – for ten cents, what do you have to lose?

Looking Forward To EMF 2024

May 29, 2024 by 10 Comments

It’s that time of year again when some parts of our community travel out into the countryside to spend time with each other under canvas in a field somewhere with power and fast internet — it’s hacker camp season. Here in Europe that means it’s the turn of the British hackers to have the year’s large event, in the form of the latest incarnation of Electromagnetic Field. We’ll be there, camera and microphone in hand, and with luck we’ll be able to bring you a flavour of the event.

The atmosphere that comes from being in the company of several thousand like minds is stimulating enough, but what makes these outdoor events special is that the villages become so much more than simply a group of geeks at a table with their laptops. Where else can one find a tea room run by a hackerspace except courtesy of MK Makerspace, or a fully functional pop-up motor racing circuit from Hacky Racers?

This year’s event badge is an interesting one, the ESP32-S3 powered and hexagon-shaped Tildagon. It’s a bold attempt to redefine the event badge away from a one-off trinket into one that lasts across multiple events, with custom “Hexpansions” like the petals on a flower, intended to have new ones appear on an event by event basis.

If you’re going to be at EMF then maybe we can join you for a pint, otherwise we’ll be bringing you the best that we find there. To whet your appetite, here’s something of the last one.

So What’s All This HaLow Long-Range WiFi About Then?

May 26, 2024 by 18 Comments

We’re all used to wireless networking, but if there’s one thing the ubiquitous WiFi on 2.4 or 5 GHz lacks, it’s range. Inside buildings, it will be stopped in its tracks by anything more than a mediocre wall, and outside, it can be difficult to connect at any useful rate more than a few tens of metres away without resorting to directional antennas and hope. Technologies such as LoRa provide a much longer range at the expense of minuscule bandwidth, but beyond that, there has been little joy. As [Andreas Spiess] points out in a recent video though, this is about to change, as devices using the so-called HaLow or IEEE 802.11ah protocol are starting to edge into the realm of affordability.

Perhaps surprisingly, he finds the 5 GHz variant to be best over a 1km test with a far higher bandwidth. However, we’d say that his use of directional antennas is something of a cheat. Where it does come into its own in his tests, though, is through masonry, with far better penetration across floors of a building. We think that this will translate to better outdoor performance when the line of sight is obstructed.

There’s one more thing he brings to our attention, which seasoned users of LoRA may already be aware of. These lower frequency allocations are different between the USA and Europe, so should you order one for yourself, it would make sense to ensure you have the appropriate model for your continent. Otherwise, we look forward to more HaLow devices appearing and the price falling even further because we think this will lead to some good work in future projects.

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How Do You Fill The 1N34 Void?

May 26, 2024 by 31 Comments

The germanium point contact diode, and almost every semiconductor device using germanium, is now obsolete. There was a time when almost every television or radio would have contained one or two of them, but the world has moved on from both analogue broadcasting and discrete analogue electronics in its lower-frequency RF circuitry. [TSBrownie] is taking a look at alternatives to the venerable 1N34A point-contact diode in one of the few places a point-contact diode makes sense, the crystal radio.

In the video below the break, he settles on a slightly more plentiful Eastern European D9K as a substitute after trying a silicon rectifier (awful) and a Schottky diode (great in theory, not so good in practice). We’ve trodden this path in the past and settled on a DC bias to reduce the extra forward voltage needed for a 1N4148 silicon diode to conduct because, like him, we found a Schottky disappointing.

The 1N34 is an interesting component, and we profiled its inventor a few years ago. Meanwhile, it’s worth remembering that sometimes, we just have to let old parts go.

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How A DOS Format Blunder Revealed Some Priceless Source Code

May 25, 2024 by 14 Comments

As those of us who worked in the consumer software world back when physical media was king can attest, when a master disc has been sent for duplication and distribution there is no turning back from whatever code is in the hands of thousands of users. Usually such worries were confined to bugs or inadvertently sending out pre-release software versions, but [Lance Ewing] is here with the story of how Sierra On-Line once inadvertently released most of the source code for their game engine.

If you have some 720k floppy disk versions of the 1988 game Space Quest II, the first disk in the set appears to have nothing out of the ordinary, but a closer look reveals that the free space on the disk reported by DOS is greater than its used space. Diving in to the disk block contents with a hex editor reveals that many of the unused blocks in fact contain C code, and some further detective work allows the recovery of a not-quite complete set of source files for the company’s AGI, or adventure game interpreter. They had been left behind when the original master disk had been emptied by deleting them, rather than by formatting it afresh.

In commercial terms this would in 1988 have been something of a disaster for Sierra had it been discovered at the time, because it was the cornerstone of their success. As it was we’re told the code sat peacefully undetected until 2016, since when it has proved invaluable to those interested in computer game archaeology. Or did it? We’ll never know if a sharp-eyed competitor snagged it, and kept quiet.

Of course, these days, there are game engines that are open source. Some of them are very modern. Others… not so much.

Is This The World’s Smallest Multichannel Voltmeter?

May 22, 2024 by 8 Comments

The instrument which probably the greatest number of Hackaday readers own is likely to be the humble digital multimeter. They’re cheap and useful, but they’re single-channel, and difficult to incorporate into a breadboard project. If you’ve ever been vexed by these limitations then [Alun Morris] has just the project for you, in the world’s smallest auto-ranging multichannel voltmeter. It’s a meter on a tiny PCB with a little OLED display, and as its name suggests, it can keep an eye on several voltages for you.

At its heart is an ATtiny1614 microcontroller on a custom PCB, but for us the part we most like lies not in that but in the prototype version made on a piece of protoboard. There’s considerable soldering skill in bending surface mount components to your will on this material, and though these aren’t quite the smallest parts it’s still something that must have required some work under the magnifier.

All of the code and hardware details can be found in the GitHub repository, and for your viewing pleasure there’s a video showing it in action which we’ve placed below.

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