Author: Jenny List

3425 Articles

Punched Cards Are In The Cloud, With This Arduino

June 20, 2023 by 15 Comments

Grizzled veterans of the computing industry will relate stories of submitting projects on stacks of punched cards, something those of us who stored their 8-bit works on audio cassettes could only imagine. But for those who fancy experimenting with the format it’s still possible to make a basic card reader using LEDs and light sensors, as [Nino Ivanov] has done using an Arduino Uno as the brains. And these aren’t just for show, each of his cards holds a LISP program that runs in a cloud service.

The Uno does the job of reading, passing its data over its USB serial port to a tablet. On the tablet the serial data is piped to a cloud API to a LISP interpreter. It seems a needlessly complex way to run a factorial program and it’s certainly a little over the top, but on the other hand we love it as a glorious combination of the old and the new. With only 23 characters per card it’s quite an impressive feat to even fit a program on the format, perhaps writing code to fit on minimalist punched cards like this could become a programming challenge in its own right for a generation accustomed to mega-and gigabytes.

If you fancy a go yourself, this isn’t the first punched card reader we’ve shown you.

Continue reading “Punched Cards Are In The Cloud, With This Arduino” →

What’s In A Slip Ring?

June 19, 2023 by 20 Comments

We know that when [Big Clive] puts up another video, the chances are we’re in for another fascinating look into a piece of tech on his bench. The latest is a slip ring assembly, and he gives it a teardown to reveal its secrets.

For most of us, the only place we encounter a slip ring is in some electric motors or alternators when it provides a connection via a conductive ring and a graphite brush from a fixed component to a rotating one. But they also appear as components in their own right wherever a rotating assembly needs an electrical contact, and it’s one of these that [Clive] has on his bench. It’s a compact unit with an impressive six conductors, and its manufacturer boldly claims that it’s good for mains voltages. We’re going with the verdict in the video below the break. That’s wishful thinking, given the size of the unit.

Inside is a rotor with six brass rings and a couple of decent little bearings, while the other half of the unit is a set of gold-plated spring contacts. There is extensive use of potting, and the verdict is that this is a surprisingly good quality component for the eBay price. We look forward to our community finding inventive uses for them. Having a ready-made unit sure beats making your own.

Continue reading “What’s In A Slip Ring?” →

Get Back Your Replaceable Batteries, Thanks To The EU

June 17, 2023 by 125 Comments

The world’s tech companies must harbour a hearty dislike for the European Union because when the many cogs of its bureaucracies turn, they find themselves with little choice but to follow or risk losing access to a huge and affluent market. There are a few areas of technology that don’t have some concessions to EU rules in their manufacturing process, and if a common charging connector or right to repair weren’t enough, they’re back for another clash with the mobile phone industry. If you hanker for the days of replaceable mobile phone batteries, you’re in luck because an EU Parliament vote has approved a set of rules covering batteries among which will be a requirement for replaceable cells in portable appliances.

We expect that the phone manufacturers will drag their feet just as some of them have over charger ports, but the greater ease of maintenance, as well as extra longevity for phones, can only be a good thing. There are a few other measures in the package, and one of them caught our eye, the introduction of a battery passport for larger industrial and EV batteries. There’s little more information in the press release, but we hope that it doesn’t inhibit their exploitation by people in our community when introduced.

We look forward to seeing more replaceable battery models appear in due course, meanwhile, you can read some of our coverage of the EU’s right-to-repair measures.

Header: Andy Melton, USA, CC BY-SA 2.0.

Your IPhone Can’t Do What This WinCE Device Can!

June 16, 2023 by 44 Comments

Most of us probably now have a smartphone, an extremely capable pocket computer — even if sometimes its abilities are disguised a little by its manufacturer. There are many contenders to the crown of first smartphone, but in that discussion it’s often forgotten that the first generally available such devices weren’t phones at all, but PDAs, or Personal Digital Assistants. The fancier ones blurred the line between PDA and laptop and were the forerunner devices to netbooks, and it’s one of these that [Remy] is putting through its paces. He makes the bold claim that it can do things the iPhone can’t, and while the two devices are in no way comparable he’s right on one point. His HP Journada 720 can host a development environment, while the iPhone can’t.

The HP was something of a turn-of-the-millennium object of desire, being a palmtop computer with a half-decent keyboard a 640×240 pixel TFT display, and 32 MB of RAM alongside its 206 MHz Intel StrongARM CPU. Its Windows CE OS wasn’t quite the desktop Windows of the day, but it was close enough to be appealing for the ’90s exec who had everything. Astoundingly it has more than one Linux distro that can run on it with some level of modernity, which is where he’s able to make the claim about the iPhone being inferior.

We remember the Journada clamshell series from back in the day, though by our recollection the battery life would plummet if any attempt was made to use the PCMCIA slot. It was only one of several similar platforms offering a mini-laptop experience, and we feel it’s sad that there are so few similar machines today. Perhaps we’ll keep an eye out for one and relive the ’90s ourselves.

The Simplest Social Engineering Hack Of Them All

June 15, 2023 by 62 Comments

Here at Hackaday we cover news and interesting features for the hacker community, with an emphasis more on the hardware side. Nevertheless we also cover stories from time to time from the broader world of security. These usually involve vulnerabilities discovered through the patient work of software or hardware researchers, and are certainly what we’d call hacking. But what about those information security breaches that aren’t hacks like that at all? What happens when the person being breached simply gives you the information?

I’ve got one, and while it’s Not A Hack, it’s definitely something that we and those outside our community need to talk about. I’m talking about the depressingly common occurrence of organisations who should know better, gifting their letterhead to all and sundry in the form of freely editable Word documents. Continue reading “The Simplest Social Engineering Hack Of Them All” →

Ham Almost Cooks ‘Dog

June 14, 2023 by 34 Comments

For those of us licensed in other countries it comes as something of a surprise to find that American radio amateurs now have to run RF exposure calculations as part of their licence requirements. [Ham Radio Crash Course] as approached this in a unique fashion, by running around 800 watts of 6-metre power into a vertical antenna festooned with hotdogs. That’s right, this ham is trying to cook some ‘dawgs! Is his station producing dangerous levels of power that might cook passers-by?

Of course, aside from a barely-warmed line along where the ‘dogs were attached to the antenna there’s no heating to be found. But we think he’s trying to make the point in the video below the break about the relative pointlessness of applying RF field limits which are definitely relevant at much higher frequencies, to hams at low frequencies.

It leaves us curious as to how that 800 watts could be efficiently transferred into the sausages and really cook them. Strapping them to a vertical is we think the equivalent of strapping anything resistive to a conductor, they do not form a significant  enough part of the circuit. We think that even six metres could cook a sausage if it could be efficiently coupled into it, so we’d suggest putting a grounded sausage up the middle of a close-wound helix.

If you have any thoughts on the RF exposure calculations, or on the best way to cook a ‘dog with 6m, we’d love to hear the, in the comments. Meanwhile, this isn’t the first piece of ‘dog-based shenanigans we’ve brought you.

Continue reading “Ham Almost Cooks ‘Dog” →

It’s Never Too Late To Upgrade Your ZX81 Keyboard

June 14, 2023 by 16 Comments

Sir Clive Sinclair’s ZX81 was a phenomenal sales success as one of the cheapest machines available in the early 1980s, but even its most fervent admirers will admit that it suffered heavily from the Sinclair economy drive. In particular that membrane keyboard was notorious for its lack of feedback, and a popular upgrade back in the day was a replacement keyboard. Now we can bring you what might be the ultimate in ZX replacement keyboards, in the form of [Brian Swetland]’s mechanical ZX81 keyboard.

The familiar 40-key layout is all there, using Cherry MX key switches and a beautiful set of custom-printed keycaps. There’s little more to a ZX keyboard than the matrix wiring, and in this case it’s all incorporated on a PCB. None of these techniques were readily available to individuals back in the ’80s, so a large piece of perfboard, key switches from an old terminal keyboard, and Letraset would have had to suffice.

We have to admit liking this project a lot, in fact we’re even tempted by a set of these keycaps for a regular keyboard just for old time’s sake. If you’re interested in the ZX81 then take a look at how we used one to help us through the pandemic.