Year: 2021

A homebrew telephone connects home and workshop.

The Calls Are Coming From Inside The House (or Workshop)

October 19, 2021 by 16 Comments

Hot on the heels of their carbon microphone build a few years ago, [Simplifier] strung up a two-phone network between the house and the workshop. Both telephones are completely DIY except for the pair of switches on the front. Each side has a bell, a microphone, and an audio transformer. Listening is done through a pair of headphones, and both users speak through a homebrew carbon microphone.

We particularly love the bell, which is made from fence post caps. Sitting between the bells and ready to strike is a ball bearing mounted on a really thick piece of wire that’s driven by an electromagnet. To make a call, you use both switches — the one on the left pulls either the bell or the microphone to ground, while the switch on the left right is used momentarily to send 6 V from the lantern battery down the 50 ft. line to the other phone to ring it. You’ll see what we mean in the demo video after the break. Check out the sound of those fence post caps!

[Simplifier] wound an audio transformer that provides the necessary impedance matching to use regular headphones as receivers. Since the homebrew microphones only need 1.5 V, [Simplifier] split the voltage across two carbon contacts placed in series. That’s still more than necessary, but [Simplifier] was able to make it work.

More recently, [Simplifier] has built a beautiful and even better carbon microphone and even hosted a back-to-basics Hack Chat.

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ESP32 Clock Pushes Outrun Graphics Over Composite

October 19, 2021 by 24 Comments

We’ve covered plenty of clocks powered by the ESP32, but this one from [Marcio Teixeira] is really something special. Rather than driving a traditional physical display, the microcontroller is instead generating a composite video signal of an animated digital clock. This could be fed into whatever device you wish, but given the 80’s synthwave style it’s pumping out, you’ll probably want to find a suitably retro CRT to do it justice.

Specifically this is a variant of the “Dali” clock, where each digit seems to melt and morph into its successor. Though his version doesn’t necessarily share code with all the previous iterations, [Marcio] does credit the developers who have pulled off similar visual tricks going all the way back to 1979. Given the vintage of this particular animation, the neon skyline and infinite scrolling grid certainly feel like a perfect fit.

Want to add a little vaporwave vibe to your own workbench? Assuming you’ve already got a 80s style CRT, all you need is an ESP32 and two wires stuck into the composite video port. One goes to ground, and the other goes to the chip’s analog pin. Once everything is powered up, you’ll be able to configure the clock with a web-based interface. It doesn’t get much easier than that.

In the documentation, [Marcio] calls out a few open source projects which were instrumental to getting his clock off the ground. The pioneering work [bitluni] did to get video out of the ESP32 is something of a given, but he also sends a hat tip to [rossumur] for his collection of 8-bit game console emulators written for the microcontroller. Projects like this are a fantastic example of what’s possible when a community works together to truly push the envelope.

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Turning Old Masks Into 3D Printer Filament

October 19, 2021 by 23 Comments

Disposable masks have been a necessity during the COVID-19 pandemic, but for all the good they’ve done, their disposal represents a monumental ecological challenge that has largely been ignored in favor of more immediate concerns. What exactly are we supposed to do with the hundreds of billions of masks that are used once or twice and then thrown away?

If the research being conducted at the University of Bristol’s Design and Manufacturing Futures Lab is any indication, at least some of those masks might get a second chance at life as a 3D printed object. Noting that the ubiquitous blue disposable mask is made up largely of polypropylene and not paper as most of us would assume, the team set out to determine if they could process the masks in such a way that they would end up with a filament that could be run through a standard 3D printer. While there’s still some fine tuning to be done, the results so far are exceptionally impressive; especially as it seems the technique is well within the means of the hobbyist.

From masks to usable filament.

The first step in the process, beyond removing the elastic ear straps and any metal strip that might be in the nose, is to heat a stack of masks between two pieces of non-stick paper with a conventional iron. This causes the masks to melt together, and turn into a solid mass that’s much easier to work with. These congealed masks were then put through a consumer-grade blender to produce the fine polypropylene granules that’re suitable for extrusion.

Mounted vertically, the open source Filastruder takes a hopper-full of polypropylene and extrudes it into a 1.75 mm filament. Or at least, that’s the idea. The team notes that the first test run of filament only had an average diameter of 1.5 mm, so they’re modifying the nozzle and developing a more powerful feed mechanism to get closer to the goal diameter. Even still, by cranking up the extrusion multiplier in the slicing software, the team was able to successfully print objects using the thin polypropylene filament.

This is only-during-a-pandemic recycling, and we’re very excited to see this concept developed further. The team notes that the extrusion temperature of 260 °C (500 °F) is far beyond what’s necessary to kill the COVID-19 virus, though if you planned on attempting this with used masks, we’d imagine they would need to be washed regardless. If the hacker and maker community were able to use their 3D printers to churn out personal protective equipment (PPE) in the early days of the pandemic, it seems only fitting that some of it could now be ground up and printed into something new.

VCF East Roars Back To Life

October 19, 2021 by 15 Comments

It didn’t take long to realize that the 2021 Vintage Computer Festival East — returning to the InfoAge Science and History Museum in Wall, New Jersey after being held virtually last year — was a massive success. In fact, the first clue came before I even got out of my car. When a volunteer came up to my window to apologetically explain that the primary parking lot was already full and I’d have to drive down the road to an overflow lot, there was no question about it; a whole lot of folks were more than ready to shake off those pandemic blues and get back to business.

They certainly picked a great event for it. While VCF East has always been a highlight of the East Coast hacker’s year, it was obvious things were really turned up to the max for this much-anticipated return to an in-person festival. With respect to all those involved in previous events, things just felt more cohesive and better organized this time around.

Veteran attendees I spoke to all felt like they were witnessing the event going through an evolutionary change into something bigger and better, while first time fliers were impressed with the buzz of activity and breadth of what was on display. In short, admiration for the event and the people working behind the scenes to make it possible was unanimous.

It’s simply not possible to adequately summarize a multi-day event like VCF East in a single post, so I won’t try to. This article, and the ones to follow it, serve only to document some of the highlights from my own personal time wandering through the sprawling InfoAge campus. Ultimately, there’s no real substitute for making the trip to Wall, NJ and experiencing this incredible event for yourself. But if that’s not an option for you, hopefully the following will give you a little taste of what the Vintage Computer Federation labors so hard over every year.

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The Quadrivium EnsembleBot Is A Labour Of Love

October 19, 2021 by 5 Comments

The Quadrivium EnsembleBot project is a mashup between old school musical instruments and the modern MIDI controlled world. Built by a small team over several years, these hand crafted instruments look and sound really nice.

The electronics side of things is taken care of with a pile of Arduinos and off-the-shelf modules, but that doesn’t mean the design isn’t well thought through, if a little more complicated than it could be in places. Control is taken care of with a PC sending commands over the USB to an Arduino 2560. This first Arduino is referred to as the Master Controller and has the immediate job of driving the percussive instruments as well as other instruments that are struck with simple solenoids. All these inductive loads are switched via opto-isolators to keep any noise generated by switching away from the microcontroller. A chain of four sixteen-channel GPIO expander modules are hung off the I2C bus to give even more opto-isolated outputs, as even the Arduino 2560 doesn’t quite have enough GPIO pins available. The are a number of instruments that have more complex control requirements, and these are connected to dedicated slave Arduinos via an SPI-to-CAN module. These are in various states of development, which we’ll be keeping our beady eyes on.

One of the more complex instruments is the PipeDream61 which is their second attempt to build a robotic pipe organ. This is powered by a Teensy, as they considered the Arduino to be a little too tight on resources. This organ has a temperature controller using an ATTiny85, in order to further relieve the main controller of such a burden and simplify the development a little.

Another interesting instrument is Robro, which is a robotic resophonic guitar which as they say is still work in progress despite how long they have been trying to get it to work. There’s clearly a fair bit of control complexity here, which is why it is taking so much fiddling (heh!) to get it work.

This project is by no means unique, lately we’ve covered controlling a church organ with MIDI, as well as a neat Arduino Orchestra, but the EnsembleBot is just so much more.

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The Low-Down On Long-Wave: Unlicensed Experimental Radio

October 19, 2021 by 70 Comments

In the 125 years since Marconi made his first radio transmissions, the spectrum has been divvied up into ranges and bands, most of which are reserved for governments and large telecom companies. Amidst all of the corporate greed, the “little guys” managed to carve out their own small corner of the spectrum, with the help of organizations like the American Radio Relay League (ARRL). Since 1914, the ARRL has represented the interests of us amateur radio enthusiasts and helped to protect the bands set aside for amateur use. To actually take advantage of the wonderful opportunity to transmit on these bands, you need a license, issued by the FCC. The licenses really aren’t hard to get, and you should get one, but what if you don’t feel like taking a test? Or if you’re just too impatient?

Well, fear not because there’s some space on the radio spectrum for you, too.

Welcome to the wonderful world of (legal!) unlicensed radio experimentation, where anything goes. Okay, not anything  but the possibilities are wide open. There are a few experimental radio bands, known as LowFER, MedFER, and HiFER where anyone is welcome to play around. And of the three, LowFER seems the most promising. Continue reading “The Low-Down On Long-Wave: Unlicensed Experimental Radio” →

The PinePhone Pro Is Here. But It’s Still Probably Not The Year Of Open-Source Linux On The Smartphone

October 19, 2021 by 82 Comments

A trope in open source commentary over the last decades has been the phrase “Is this the year of Linux on the desktop?”, as though the open source OS will finally break through and challenge Windows. In fact the process has been one of stealth rather than explosive growth, as the likes of ChromeOS with its Linux underpinnings become the go-to choice for an inexpensive consumer laptop. In the phone arena the same has happened with Android, as most users have no idea that a Linux foundation lies beneath their Samsung Galaxy or Google Pixel.

Fully open-source via Android on the phone has been very slow to arrive, but could that be changed by the arrival of Pine64’s PinePhone Pro? The new device will be available alongside their existing PinePhone, and will continue the dream of a fully open-source mobile phone with its increased-specification hardware.

As much as the specs of one black slab versus another matter, at its heart is a 1.5 GHz Rockchip RK3399S hexa-core SoC alongside 4 GB of dual-channel LPDDR4 RAM. This compares well to the original PinePhone’s quad-Core Allwinner A64 at 1.152 GHz and 3 GB LPDDR3 RAM, so it’s clear that there is plenty of capability in this phone.

Any phone whether open-source or not will however live or die on the quality of its software and support, so for this model to be a real success outside the realm of extreme open-source devotees we think that Pine64 will need to be prepared to up their game when it comes to what happens after hardware delivery. It’s fair to say that some of their previous products have been a little lacklustre in this department, with hardware bugs remaining unfixed. Their approach of relying on the community of users to deliver software support has not so far returned a stable experience for users of the original PinePhone. We understand that their intention is to provide a developer’s phone, but developers need to place phonecalls and take pictures too.

We’ve seen some PinePhone owners commenting to this effect, and though we’re fans of Pine64 and like what they are trying to do, we have to admit that those users have a point. If they were prepared to put some effort into software development to the extent of providing an official OS image with let’s say Plasma Mobile, a working phone app, a working web browser, and responsive phone features such as instant on and off, even at the expense of charging more for the phone itself, we think that they’ll be on to a winner. Otherwise they’ll remain as the really cool open-source phone that only your kernel-wizard friends own, and even then they use a Google Pixel as their everyday phone. Please Pine64, prove us wrong!

Last month our colleague Brian Cockfield took us on a tour of his PinePhone.