For all that “should have used a 555” is a bit of a meme around here, there’s some truth to it. The humble 555 is a wonderful tool in the right hands. That’s why it’s wonderful to see this all-analog stylus synth project by EE student [DarcyJ] bringing the 555 out for the new generation.

The project is heavily inspired by the vintage stylophone, but has some neat tweaks. A capacitor bank means multiple octaves are available, and using a ladder of trim pots instead of fixed resistors makes every note tunable. [Darcy] of course included the vibrato function of the original, but no, he did not use a 555 for that, too. He used an RC oscillator. He put a trim pot on that, too, to control the depth of vibrato, which we don’t recall seeing on the original stylophone.

The writeup is very high quality and could be recommended to anyone just getting started in analog (or analogue) electronics– not only does [Darcy] explain his design process, he also shows his pratfalls and mistakes, like in the various revisions he went through before discovering the push-pull amplifier that ultimately powers the speaker.

Since each circuit is separately laid out and indicated on the PCB [Darcy] designed in KiCad for this project. Between that and everything being thru-hole, it seems like [Darcy] has the makings of a lovely training kit. If you’re interested in rolling your own, the files are on GitHub under a CERN-OHL-S v2 license,  and don’t forget to check out the demo video embedded below to hear it in action.

Of course, making music on the 555 is hardly a new hack. We’ve seen everything from accordions to paper-tape player pianos to squonkboxes over the years. Got another use for the 555? Let us know about it, in the inevitable shill for our tip line you all knew was coming.

 

The video (embedded below) by [TechAltar] is titled “1 Month without US tech giants“, but it could have been titled “1 Month with Open Source Tools” — because, as it turns out, once you get out of the ecosystem set up by the US tech giants, you’re into the world of open source software (OSS) whether you want to be or not.

From a (German-made) Tuxedo laptop running their own Linux distro to a Fairphone with e/OS (which is French), an open version of Android, [TechAlter] is very keen to point out whenever Europeans are involved, which is how we learned that KDE has a physical headquarters, and that it’s in Berlin. Who knew?

He also gives his experiences with NextCloud (also German), can be used as an OSS alternative Google Workspaces that we’ve written about before, but then admits that he was the sole user on his instance. To which one must question: if you’re the sole user, why do you need a cloud-based collaborative environment? To try it out before getting collaborators involved, presumably.

Regardless what you think of the politics motivating this video, it’s great to see open source getting greater traction. While [TechAltar] was looking for European alternatives, part of the glory of open source is that it doesn’t matter where you’re from, you can still contribute. (Unless you’re Russian.) Have you found yourself using more open source software (or hardware) of late? Do you think the current political climate could lead to a broadening of its reach? Is this the year of the linux desktop? Let us know what you think in the comments.

If you’ve ever looked at widgets on your iPhone, you’ve probably noticed they’re largely static, save for a few first-party apps. By and large, third party developers are not supposed to be able to animate them. However, [Bryce Bostwick] found a workaround.

You might be confused as to the idea of animated widgets, but it’s quite simple. For example, think of a clock app with a widget in which the hands always display the current time, or a calendar app with an icon that shows the current date. Apple’s own apps have long been able to do this, but the functionality has mostly been locked out for third parties.

One way to get around this limitation is by using a timer feature baked into the widget functionality. The timer tool is one of the few ways that third-party apps are allowed to do animation. By running a timer with a custom font, you can display various graphical elements instead of numbers counting down to create a hacky animation that updates every second.

However, there are even more advanced techniques that can get you faster, smoother animations. [Bryce] breaks down the private techniques used to rotate the clock hands on Apple’s own widget, and how to use those tools for your own purposes. It takes some sneaky Xcode tricks and a bit of math to make it fully flexible for doing arbitrary animations, but it works surprisingly well.

Will this backdoor last ? Well, Apple is always updating and changing iOS and its associated software, so don’t expect it to work forever.

Thanks to [gnif] for the tip!

These days, if you’re walking around with a cellphone, you’ve basically fitted an always-on tracking device to your person. That’s even more the case if there happens to be an eavesdropping device in your vicinity. To combat this, the Electronic Frontier Foundation has created Rayhunter as a warning device.

Rayhunter is built to detect IMSI catchers, also known as Stingrays in the popular lexicon. These are devices that attempt to capture your phone’s IMSI (international mobile subscriber identity) number by pretending to be real cell towers. Information on these devices is tightly controlled by manufacturers, which largely market them for use by law enforcement and intelligence agencies.

To run Rayhunter, all you need is an Orbic RC400L mobile hotspot, which you can currently source for less than $30 USD online. Though experience tells us that could change as the project becomes more popular with hackers. The project offers an install script that will compile the latest version of the software and flash it to the device from a  computer running Linux or macOS — Windows users currently have to jump through a few extra hoops to get the same results.

Rayhunter works by analyzing the control traffic between the cell tower and the hotspot to look out for hints of IMSI-catcher activity. Common telltale signs are requests to switch a connection to less-secure 2G standards, or spurious queries for your device’s IMSI. If Rayhunter notes suspicious activity, it turns a line on the Orbic’s display red as a warning. The device’s web interface can then be accessed for more information.

While IMSI catchers really took off on less-secure 2G networks, there are developments that allow similar devices to work on newer cellular standards, too. Meanwhile, if you’ve got your own projects built around cellular security, don’t hesitate to notify the tipsline!

If we asked you to name Alexander Graham Bell’s greatest invention, you would doubtless say “the telephone”; it’s probably the only one of his many, many inventions most people could bring to mind. If you asked Bell himself, though, he would tell you his greatest invention was the photophone, and if the prolific [Nick Bild] doesn’t agree he’s at least intrigued enough to produce a replica of this 1880-vintage wireless telephone. Yes, 1880. As in, only four years after the telephone was patented.

It obviously did not catch on, and is not the sort of thing that comes to mind when we think “wireless telephone”. In contrast to the RF of the 20th century version, as you might guess from the name the photophone used light– sunlight, to be specific. In the original design, the transmitter was totally passive– a tube with a mirror on one end, mounted to vibrate when someone spoke into the open end of the tube. That was it, aside from the necessary optics to focus sunlight onto said mirror. [Nick Bild] skips this and uses a laser as a handily coherent light source, which was obviously not an option in 1880. As [Nick] points out, if it was, Bell certainly would have made use of it.

The receiver is only slightly more complex, in that it does have electronic components– a selenium cell in the original, and in [Nick’s] case a modern photoresistor in series with a 10,000 ohm resistor. There’s also an optical difference, with [Nick] opting for a lens to focus the laser light on his photoresistor instead of the parabolic mirror of the original. In both cases vibration of the mirror at the transmitter disrupts line-of-sight with the receiver, creating an AM signal that is easily converted back into sound with an electromagnetic speaker.

The photophone never caught on, for obvious reasons — traditional copper-wire telephones worked beyond line of sight and on cloudy days–but we’re greatful to [Nick] for dredging up the history and for letting us know about it via the tip line. See his video about this project below.

The name [Nick Bild] might look familiar to regular readers. We’ve highlighted a few of his projects on Hackaday before.

AI Picasso is a free mobile app which lets you generate AI images and art using Stable Diffusion. The app is free to use but is monetized by 10 second in-app ads which can be rather annoying. There are still a nice range of features and the image generation is relatively fast. Since there are […]

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Simple Phones ensures that you never miss a call from a customer with its AI-powered call answering service. It offers call routing and logging features, transparent records of all calls, and affordable pricing with no long-term commitments. You can easily manage your account on the go with your mobile device, and Simple Phones is committed […]

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