Dutch Hackerspaces At Ten Years Old: Celebrating A Community With A Special Map

February 6, 2020 by Jenny List 4 Comments

The exotic cruise destination of Hoek van Holland Haven.

A couple of months ago I wrote a piece about the evolution of hackerspaces, and mentioned that I’d be attending a party for a hackerspace birthday. As I write this that party was last weekend, and it was celebrating both the birthday of RevSpace in the Hague, and the tenth anniversary of hackerspaces in the Netherlands. After a relaxing ocean cruise across the North Sea and a speedy train ride I found myself in RevSpace with a bottle of Club-Mate in my hand, hanging out with not only the locals but a selection of others from all across northwestern Europe and beyond. RevSpace is an exceptionally well-organised hackerspace with a large membership, so there was plenty to talk about and a lot of interesting projects to look at.

There was a short programme of talks in Dutch, covering hackerspace history and interviewing a panel of hackerspace founders. I am told that these may make their way online with an English translation in due course, and should be worth looking out for. Then there was an epic-scale barbecue, an old-school rave with Gameboy chiptunes and analogue synth EDM among other delights, and the chance for an evening’s socialising with the rest of the attendees. Continue reading “Dutch Hackerspaces At Ten Years Old: Celebrating A Community With A Special Map” →

An EV Motor Controller Home Build

February 5, 2020 by Jenny List 18 Comments

Many of us will have experimented with brushless motors, and some of us will have built our own controllers rather than using an off-the-shelf part. Doing so is a good way to understand their operation, and thus to design better brushless motor powered projects. Few of us will have gone as far as [etischer] though, and embarked upon building our own controller for a 300V 90kW traction motor.

The tricky part of a high power brushless motor controller lies not in the drive but in the high-power switching arrangements. He’s using a bank of IGBTs, and to drive them he’s using a smaller industrial variable frequency drive controller with its own output transistors removed. He takes us through some of the development of the system, including showing him blowing up a set of IGBTs through having too much inductance between transistors and reservoir capacitor, and then to his final design.

This is part of a project VW first converted ten years ago, and as part of a series of videos he’s produced one going through the whole project. It’s a fascinating breakdown of the parts required for an EV conversion, and the teething troubles he’s encountered along the way.

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A Mini SDR Receiver Using An Audio DSP

February 1, 2020 by Jenny List 18 Comments

Software defined radio or SDR is the most exciting frontier in the field of radio, transferring as it does all signal functions from the analogue to the digital domain. Radios using SDR techniques can be surprisingly straightforward and easy to understand, and [Ray Ring]’s little SDR receiver manages to combine this with the novel use of an audio DSP rather than a computer to perform its SDR functions.

The front end is a conventional enough direct conversion design with an Si5531 clock generator providing I and Q phase-shifted local oscillator signals to a TS3A5017 analogue switch used as a mixer. An unexpected presence is an LTC6252 op-amp as an RF amplifier, but the special part comes after the I and Q baseband signals have been filtered. The SDR part of this receiver is an audio DSP, but it’s one that might not be an immediate choice. The Spin Semiconductor FV-1 is a dedicated digital reverb chip for musical effects boxes, but it comes with the feature that its internal DSP core can access custom code from an external ROM. [Ray] has written his own code for demodulation of AM, USB, and LSB signals rather than musical effects, and used the device’s left and right audio channels to process I and Q quadrature signals. The use of a single purpose chip to do something its designers never intended gives it the essence of a good hack, and we’re mightily impressed at his spotting the potential for an SDR in a musical effect. Hear it in action in the video below the break.

Meanwhile if the operation of a receiver such as this one is a mystery to you, we published a handy primer back in 2017.

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What Everyone Else Did With Eight Bits, The Germans Did With Only One

February 1, 2020 by Jenny List 51 Comments

In the 1980s there was an impetus for the first time for young people to be equipped with computer literacy. A variety of different educational programmes were launched, typically involving a collaboration between a computer manufacturer and a broadcaster, and featuring BASIC programming on one of the 8-bit home computers of the day. One such educational scheme was a bit different though, the German broadcaster WDR produced an educational series using a modular computer featuring an unusual 1-bit processor that was programmed in hexadecimal machine code. [Jens Christian Restemeier] has produced a replica of this machine, that is as close to the original as he can make it. (Video, in German, embedded below.)

The computer is called the WDR-1, and had its origin in a kit machine before it was taken up by the broadcaster. The unusual 1-bit processor is a Motorola MC14500, which was produced from 1977 onwards for industrial control applications. He takes the viewer in the video below the break through the machine’s parts, explaining the purpose of each daughter card and the motherboard. Lacking an original to copy he instead worked from photographs to replicate the chip placements of the original, substituting pin headers for the unusual sockets used on the 1980s machines. Take a look at his video, below the break.

More information on the WDR-1 can be found online in German (Google translate link). Meanwhile we’ve featured the MC14500 before, in a small embedded computer.

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A Nano With An Otter’s Bite

February 1, 2020 by Jenny List 22 Comments

The would-be microcontroller experimenter is now faced with a bewildering array of choices when it comes to a tiny development board for their projects. Everything from descendants and clones of the original Arduino through to full-fat Linux powerhouses such as the Raspberry Pi Zero and similar boards can be had, and often for a reasonable price.

A new entrant has now joined the fray, the OtterPill is an STM32F072-based board with an Arduino-Nano-like pinout, and it comes from the bench of [Jana Marie]. With so many competitors you might ask yourself what it can offer, and it would be a valid point given that a Nano clone can be had for relative pennies. Aside from the Nano shield compatibility and extra power of the ARM Cortex M0 then, it’s an open source development board with USB-PD included from its USB-C socket, and with some elite BoM wizardry she’s managed to get the cost of its components to below three dollars. A USB-PD example firmware is available and a blank firmware is on its way. For now the board exists only in prototype form, but she’s putting together a production run if you would like one too. We saw an early development of it at eth0 back in the autumn, and given the progress since then we’re sure that we won’t have to wait for long.

Regular readers will recognise [Jana Marie]’s work, because otter-themed boards have made their way to these pages before. Our most recent ones were the USB-C replacement board bringing USB-PD to the TS-100 soldering iron, and a nifty little USB board for addressable LEDs.

This Crossbow Fires Cannonballs!

January 31, 2020 by Jenny List 9 Comments

The would-be invader of a mediaeval kingdom could expect to face some stern opposition from a variety of formidable weaponry. Making modern versions of these deadly curiosities seems to be a popular pursuit, and the bug has bitten [Turbo Conquering Mega Eagle], who’s created what he calls a “Stonebow”, a crossbow on steroids that fires stones or large ball bearings with considerable force.

It uses a couple of leaves from automotive springs, mounted in a welded steel riser with two strings and a pouch for the projectile. The barrel is an oak fencing post, and at its other end is a cocking lever which also forms a stock, and a cleverly designed trigger mechanism. The projectile is loaded, the bow is cocked, and it is fired at a scrap Land Rover radiator in which it places a satisfying impact mark.

Despite two successful firings it’s evident that so much force isn’t easy to contain. The crimps that secure the strings aren’t up to the job, and neither is the oak fence post, which has cracked at the end. We trust that our Essex hacker friend will return having fixed these flaws, and more defenceless scrap car parts will be sacrificed for our entertainment.

We’ve featured [Turbo Conquering Mega Eagle] before, most recently building a mini-bike for his youngsters. Meanwhile, enjoy the Stonebow in the video below the break.

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This Is It For The Particle Mesh Network

January 30, 2020 by Jenny List 24 Comments

The long-held dream of wireless network hackers everywhere is to dispense with centralised network infrastructure, and instead rely on a distributed network in which the clients perform the role of distribution and routing of traffic. These so-called mesh networks promise scalability and simplicity on paper, but are in practice never as easy to implement as the theory might suggest. Much venture capital has been burned over the years by startups chasing that particular dream, yet most of our wireless connectivity still follows a hub topology.

An exciting development in our sphere concerning mesh networking came in early 2018, when Particle, the purveyors of wireless-equipped dev boards, launched their third generation of products. These offered mesh networking alongside their other features, but this week they have announced that they’ll no longer be developing that particular side of their offering. The Wi-Fi-equipped Argon and Cellular-equipped Boron will remain on sale, but they will henceforth discontinue the mesh-only Xenon. Existing owners of the now orphaned board will be compensated with store credit.

Their rationale for discontinuing mesh networking is interesting, and reflects on the sentiment in our first paragraph. Mesh networking is hard, and in particular their attempt to make it work with zero configuration was simply not successful. But then they talk about the realisation that maybe mesh networking was not the right solution for the IoT applications the boards were being used in, and perhaps another technology such as LoRa would be more appropriate.

So the mesh experiment from Particle is over, but the company and its connected dev boards are very much still with us. We salute them for being bold enough to try it, and we wonder when we’ll next find a piece of similar mesh networking hardware.