We’ve become used to software-defined radio as the future of radio experimentation, and many of us will have some form of SDR hardware. From the $10 RTL USB sticks through to all-singing, all-dancing models at eye-watering prices, there is an SDR for everyone.
What about the idea of an SDR without any external hardware? Instead of plugging something into your Raspberry Pi, how about using the Pi itself, unmodified? That’s just what the Nexmon SDR project has achieved, and this has been made possible through clever use of the on-board Broadcom 802.11ac WiFi chip. The result is a TX-capable SDR, albeit one only capable of operating within the 2.4 GHz and 5 GHz spectrum used by WiFi.
The team had previously worked extensively with the chipset in the Nexus 5 phone, and the SDR extension was first available on that platform. Then along came the Raspberry Pi 3 B+ with a similar-enough WiFi chipset that the same hack was portable to that platform, et voilá: WiFi SDR on a Pi 3 B+.
If you’ve not looked at the Pi 3 B+ we’d like to direct you to our review. If you don’t have a Nexus 5 kicking around, and you’d like to do some WiFi-band SDR work, it’s looking like an amazing deal.
A reasonable selection of the Hackaday readership will have had their first experiences of computing on an 8-bit machine in a black case, with the word “Sinclair” on it. Even if you haven’t work with one of these machines you probably know that the man behind them was the sometimes colourful inventor Clive (now Sir Clive) Sinclair.
The finest in 1950s graphic design, applied to electronics books.
He was the founder of an electronics company that promised big results from its relatively inexpensive electronic products. Radio receivers that could fit in a matchbox, transistorised component stereo systems, miniature televisions, and affordable calculators had all received the Sinclair treatment from the early-1960s onwards. But it was towards the end of the 1970s that one of his companies produced its first microcomputer.
At the end of the 1950s, when the teenage Sinclair was already a prolific producer of electronics and in the early stages of starting his own electronics business, he took the entirely understandable route for a cash-strapped engineer and entrepreneur and began writing for a living. He wrote for electronics and radio magazines, later becoming assistant editor of the trade magazine Instrument Practice, and wrote electronic project books for Bernard’s Radio Manuals, and Bernard Babani Publishing. It is this period of his career that has caught our eye today, not simply for the famous association of the Sinclair name, but for the fascinating window his work gives us into the state of electronics at the time.
If you study the specifications of the ESP8266 WiFi-enabled microcontroller, you will notice that it features an I2S audio interface. This is a high-speed serial port designed to deliver 16-bit audio data in a standard format, and has its origins in consumer audio products such as CD players. It would be usual to attach a dedicated DAC to an I2S interface to produce audio, but [Jan Ostman]’s synthesiser projects eschew that approach, and instead do the job in software. His I2S interface pushes out a pulse density modulated data stream in the same manner as a 1-bit DAC, meaning that the only external components required to produce audio are a simple low-pass filter. He’s posted a video of the synth in action, which we’ve placed below the break.
The example he gives us is a basic clone of a Roland 909 drum machine, and he takes us through the code with extensive examples including MIDI. He’s using the Wemos D1 Mini board, but the same could be replicated with many other ESP8266 platforms.
We’re following our usual Bring-a-Hack style format, so come along and hang out with members of the London Hackaday community, and if you have a project to bring along then don’t be shy as we’d love to see it. And especially if you have a Hackaday Prize entry to show then we’d particularly like to see it. You never cease to amaze us with the work you do, be it the simplest of hacks or the most technically advanced. Just one thing though, if you bring something, make sure it’s handheld or portable enough to easily sit on a pub tabletop, space may be limited.
In attendance will be Tindie’s [Jasmine Brackett] and Hackaday’s [Jenny List], as well as quite a few of our community regulars. What better way could there be to spend a spring Sunday afternoon in London?
But what if you can’t make London, and face the prospect of missing out on us entirely? Fortunately, this one is not the only meetup we have planned, we’re heading to Nottingham and Cambridge on the 18th and 19th of April, respectively, and might even squeeze in another date if we can.
On Saturday, the Hackaday Community from across Ireland and other parts of Europe poured into the performance hall at Dublin’s Project Arts Centre for a massive collection of talks. From rediscovering century’s old technology, to cutting edge research projects, we heard talks from dozens of attendees on the technology that is interesting them most right now.
Choosing what to share about last weekend’s Uncon has been a particularly taxing process. So many and varied were the projects presented, and such was their high standard, that a writer faces a significant challenge to fit them into a single report. But we’ll give it a try. Read on for highlights of what was a weekend we will remember forever.
[Rachel]’s about to lull us into a false sense of security with talk of fashion, then go for the eyeballs!
From Wearables to Lab-Grown Eyeballs
Dublin by early April has lost some of winter’s chill, but the sun hadn’t regained control enough for the populace to have shed their coats and boots. It was in a slightly damp Temple Bar then that the Hackaday faithful convened at the Project Arts Centre, temporarily forsaking for us its role as one of Ireland’s most cutting-edge contemporary performing arts venues. We’d spent the previous day rounding up what seemed like Ireland’s entire stock of snack food to keep everyone happy, so it was into the upstairs performance hall for the day’s festivities. After putting in a talk topic and stopping by the swag table for goodies from our sponsor, DesignSpark, we all packed into the hall and began the Uncon.
First to brave the floor was [Rachel “Konichiwakitty” Wong], who started by talking about her interest in and flair for wearable electronics applied to fashion. This is not however what she does for a living, and she soon switched from the kawaii to the everyday work of a stem cell research scientist. This section of her talk was entitled “The Future Of Medicine, stem cells, tissue engineering, off-the-shelf pick-n-mix organs”. Because of the work being done by people like her our hospitals may one day be able to prescribe custom 3D-printed organs for their patients, and her talk was a fascinating overview of that field for those of us who can not grow eyeball tissue on our benches.
There followed the exciting Unconference format, in which attendees were scheduled on-the-fly in four talk sessions throughout the day. Each deliver a seven-minute presentation and although it’s not compulsory to give an Unconference talk, there were definitely more than enough people wanting to give it a go. It’s impossible to mention them all in a single Hackaday piece, but here follows a selection of the many that caught our eye.
Judging by the number of compilations that have been put online, one of the not-so-secret vices of the YouTube generation must be the watching of crash videos. Whether it is British drivers chancing their luck on level crossings, Russians losing it at speed on packed snow, or Americans driving tall trucks under low bridges, these films exert a compelling fascination upon the viewing public intent on deriving entertainment from the misfortunes of others. The footage is often peripheral or grainy, having inevitably been captured by a dashcam or a security camera rather than centre-stage on a broadcast quality system with professional operation. You can’t predict when such things will happen.
There was one moment, back in 1984, when predicting a major crash was exactly what you could do. It was a national event, all over the TV screens, and one which was watched by millions. The operators of British nuclear power stations wished to stage a public demonstration of how robust their transport flasks for spent nuclear fuel rods were, so after all the lab tests they could throw at one they placed it on a railway test track and crashed a 100mph express train into it.
Water escaping during drop test.
This was as much a PR stunt as it was a scientific endeavour, and they lost no time in promoting it across all media. The film below the break was part of this effort, and takes us through the manufacture of the flask forged in one piece from huge billets of steel, before showing us the tests to which it was subjected. The toughest of these, a drop-test onto a corner of a fully laden flask, resulted in a small escape of the water contained within it. It was thus decided to conduct the ultimate test to ensure full public confidence in nuclear transport.
The Old Dalby test track is a section of a closed-to-passengers line in the English Midlands that was retained by British Railways as a proving ground for new locomotives. In the ultimate test of rail transport for nuclear waste, a flask was placed on its side across a piece of the track, and a train formed of a withdrawn 1960s locomotive and a short rake of 1950s carriages was accelerated without a driver over several miles to 100mph.
An instant before impact, we see the underside of the derailed car. The flask is between it and the locomotive.
[Nigel Harris] for Rail magazine wrote an almost funerial description of the destruction of locomotive 46009 25 years later in 2009, and as he reported the flask survived with only superficial damage and a tiny loss in pressure. The event was hailed as a success by the nuclear industry, before fading from the public consciousness as nuclear power station operators prefer to remain out of the news.
It is questionable how much the Old Dalby crash was for the cameras and the public, and how much it was for the scientists and engineers. But such destructive tests do serve as a means to gain vital test data that could not be harvested any other way, and have been performed more than once in the aviation industry. Later in the same year a Boeing 720 was crashed for science in the USA, while more recently in 2012 a Boeing 727 was crashed in Mexico.
Crashing an express train into a nuclear flask is something not likely to be seen again, it was a one-off event. But one thing’s for sure, our inability to turn away from watching a train wreck is nothing new. YouTube and ubiquitous cameras certainly make crashes available with a few keystrokes. But from the 1984 cask crash test, to the the spectacle of Crush, Texas back in 1896, the sheer power shown in these crashes seems to have a siren song effect on us.
This unholy lovechild of a cheap solder sucker and an even cheaper soldering iron is the HBTool HB-019 desoldering iron. It came to me for the princely sum of five pounds ($7). So for somewhere between the cost of a pint of foaming ale and the pub’s pie and mash I’d eat alongside it, what had I got?
Regular Hackaday readers will be familiar with my penchant for ordering cheap tools and other electronic gizmos from the usual suppliers of Far Eastern tech, and subjecting them to review for your entertainment and edification. Sometimes the products are so laughably bad as to be next-to-worthless, other times they show enough promise to be of use, and just occasionally they turn out to be a genuine diamond in the rough, a real discovery. This is no precious stone, but it still makes for an entertaining review. Continue reading “Reviewing The HBTool HB-019 Desoldering Iron: It Probably Won’t Shock You”→
![[Rachel]'s about to lull us into a false sense of security with talk of fashion, then go for the eyeballs!](https://hackaday.com/wp-content/uploads/2018/04/rachel-konichiwakitty.jpg)
