It’s obvious this was a controversial product, and maybe the Hackaday verdict had been a little summary based on the hammer aspect of the story. So to get further into what all the fuss had been about I ordered a Pi Zero and the solderless pin kit to try for ourselves.
We have all been beneficiaries of the boom in availability of cheap imported electronics over the last decade. It is difficult to convey to someone under a certain age the step change in availability of parts and modules that has come about as a result of both the growth of Chinese manufacturing and Internet sales that allow us direct access to sellers we would once only have found through a lengthy flight and an intractable language barrier.
So being able to buy an ESP8266 module or an OLED display for relative pennies is good news, but there is a downside to this free-for-all. Not all the products on offer are manufactured to legal standards wherever in the world we as customers might be, and not all of them are safe to use. We’ve all seen teardowns of lethal iPhone charger knock-offs, but this week the ARRL has highlighted an illegal import that could take being dangerous to a whole new level as well as bring an already beleaguered section of our community to a new low.
The products the radio amateurs are concerned about are video transmitters that work in the 1.2GHz band. These are sold for use with FPV cameras on multirotors, popularly referred to as drones, and are also being described as amateur radio products though their amateur radio application is minimal. The ARRL go into detail in their official complaint (PDF) about how these devices’ channels sit squarely over the frequencies used by GLONASS positioning systems, and most seriously, the frequencies used by the aircraft transponders on which the safety of our air traffic control system relies.
The multirotor community is the unfortunate recipient of a lot of bad press, most of which is arguably undeserved and the result of ignorant mass media reporting. We’ve written on this subject in the past, and reported on some of the proposals from governments which do not sound good for the enthusiast. It is thus a huge concern that products like those the ARRL is highlighting could result in interference with air traffic, this is exactly not the association that multirotor fliers need in a hostile environment.
The ARRL complaint highlights a particular model with a 5W output, which is easily high enough to cause significant interference. It is however just one of many similar products, which a very straightforward search on the likes of AliExpress or eBay will find on sale for prices well under $100. So if you are concerned with multirotors we’d urge you to ensure that the FPV transmitters you or your friends use are within the legal frequencies and power levels. We’re sure none of you would want an incident involving a manned aircraft on your conscience, nor would you relish the prospect of the encounter with law enforcement that would inevitably follow.
There are a host of tiny plug-top computers available for the experimenter who requires an all-in-one mains-powered computing platform without the annoyance of a full-sized PC or similar. But among the various models there has always been something missing, a plug-top Raspberry Pi. To address that gap in the market, [N-O-D-E] has created a fusion of Pi and plug using the official Raspberry Pi PSU accessory and a Raspberry Pi Zero, with a UUGear Zero4U USB hub sandwiched between the two.
It’s a pretty straightforward and simple build, the back of the PSU is formed into a flat surface with a bit of Sugru, then the power cable is stripped back to its wires which are then connected to the power pins on the USB hub. The hub is then attached to the Sugru — he doesn’t say how, but we suspect double-sided tape — and the Pi is mounted on top of the hub. Pogo pins make the required connections to the pads on the underside of the computer, so it can be removed and replaced at will.
The result is a useful addition to your Pi arsenal, one that could be used for a host of little stand-alone devices. It could use a cover, however we suspect a 3D printer owner could create themselves one with relative ease. The full description is shown in the video below the break.
The Raspberry Pi single board computer has been an astounding success since its launch nearly five years ago, to the extent that as of last autumn it had sold ten million units with no sign of sales abating. It has delivered an extremely affordable and pretty powerful computer into the hands of hobbyists, youngsters, hackers, engineers and thousands of other groups, and its open-source Raspbian operating system has brought a useful Linux environment to places we might once have thought impossible.
The previous paragraph, we have to admit, is almost true. The Pi has sold a lot, it’s really useful and lots of people use it, but is Raspbian open-source? Not strictly. Because the Broadcom silicon that powers the Pi has a significant amount of proprietary tech that the chipmaker has been unwilling to let us peer too closely at, each and every Raspberry Pi operating system has shipped with a precompiled binary blob containing the proprietary Broadcom code, and of course that’s the bit that isn’t open source. It hasn’t been a problem for most Pi users as it’s understood to be part of the trade-off that enabled the board’s creators to bring it to us at an affordable price back in 2012, but for open-source purists it’s been something of a thorn in the side of the little board from Cambridge.
This is not to say that all is lost on the blob-free Pi front. Aided by a partial pulling back of the curtain of secrecy by Broadcom in 2014, work has quietly been progressing, and we now have the announcement from [Kristina Brooks] that a minimal Linux kernel can boot from her latest open firmware efforts. You won’t be booting a blob-free Raspbian any time soon as there are bugs to fix and USB, DMA, and video hardware has still to receive full support, but it’s a significant step. We won’t pretend to be Broadcom firmware gurus as we’re simply reporting the work, but if it’s your specialty you can find the code in its GitHub repository. Meanwhile, we look forward to future progress on this very interesting project.
We reported on the partial Broadcom release back in 2014. At the time, the Raspberry Pi people offered a prize to the first person running a native Quake III game on their hardware, sadly though they note the competition is closed they haven’t linked to the winning entry.
There is a rule of thumb to follow when looking at product announcements at the fringes of the motor industry that probably has something in common with crowdfunding campaigns. If the photographs of the product are all renders rather than real prototypes, walk away. It is said that small volume vehicle production is a space that attracts either crooks or dreamers, and parting with your money to either can be a risky business. So when yet another electric vehicle platform makes its debut it’s always worth looking, but too often the rendered images outnumber anything from the real world and you know you’ll never see one on the road.
It is with interest then that we note an exciting announcement made last week at CES, that the French carmaker Renault are to release an open-source vehicle platform. It is called the POM, and it is based upon their existing Twizy electric buggy platform. If this last point causes you to snort with derision because the Twizy is a tiny and not very fast in-line two-seater with awful weather protection better suited to the French Riviera than an American Interstate, remember that the car itself is not the point of this exercise at this stage. Instead the access to the technology will spark fresh innovation in the open electric vehicle sector that will transfer into better systems for more practical open source vehicles in the future. (Incidentally, we’re told by people who’ve tried the Twizy that it can be something of an unexpected gem to drive. It seems the lowish top speed doesn’t matter in the twisties when you have a low centre of gravity and quite impressive acceleration in a tiny machine.)
Partnered with Renault are OSVehicle, ARM, Pilot Automotive, a manufacturer of automotive accessories, and Sensoria, who will be working on wearable accessories. It’s probable that you won’t see many POMs on the road if you don’t live in a territory that already has the Twizy, but it’s certain you’ll see its technological legacy in other vehicles.
Mass storage presents a problem for those involved in the preservation of older computer hardware. While today’s storage devices are cheap and huge by the standards of decades ago their modern interfaces are beyond the ability of most older computers. And what period mass storage hardware remains is likely to be both unreliable after several decades of neglect, and rather expensive if it works due to its rarity.
The Domesday Project 86 team face this particular problem to a greater extent than almost any others in the field, because their storage device is a particularly rare Philips Laser Disc drive. Their solution is the BeebSCSI, a small board with a CPLD and an AVR microcontroller providing host adaptor and SCSI-1 emulation respectively for a modern micro-SD card.
An original BBC Domesday set-up. Regregex [CC BY 3.0], via Wikimedia Commons.1986 saw the 900th anniversary of the Domesday Book, a survey and inventory of his new kingdom commissioned in 1086 by the Norman king of England, William the Conqueror. One of the ways the event was marked in 1986 was the BBC Domesday Project, a collaboration between the BBC, several technology companies including Acorn and Philips, and a huge number of volunteers from the general public and the British school system. Pictures, video, and text were gathered relating to locations all over the country, and the whole was compiled with a not-quite-hypertext interface onto a set of Laser Disc ROMs. The system required the upgraded Master version of the 6502-based BBC Micro, a SCSI interface, and a special Laser Disc player model manufactured by Philips for this project alone. The hardware was expensive, rare, and unreliable, so few of its contributors would have seen it in action and it faded from view to become a cause celebre among digital archivists.
There have been several resurrections of the project over the years, including one from the BBC themselves which you can browse online. What makes this project different from the others is that it strives to present the Domesday experience as it was originally intended to be viewed, on as far as possible the original hardware and with the original BBC Micro interface. Many original parts such as BBC Master systems are relatively easy to source in 2016, but the special Laser Disc player is definitely not. This board replaces that impossible link in the chain, and should allow them to present a glimpse of 1986 in more than just the on-screen information.
Our Hackaday readership represent a huge breadth of engineering experience and knowledge, and we get a significant number of our story tips from you. For instance, today we are indebted to [sonofthunderboanerges] for delivering us a tip in the comment stream of one of our posts, detailing an antenna created by coupling RF into a jet of sea water created with a pump. It’s a few years old so we’re presenting it as an object of interest rather than as a news story, but it remains a no less fascinating project for that.
The antenna relies on the conductivity of sea water to view a jet of water as simply another conductor to which RF can be coupled. The jet is simply adjusted by altering the flow rate until it is a quarter wavelength long at the desired frequency, at which point it is a good analogue of a metal whip antenna. The RF is coupled at the base by a ferrite cored transformer that clips around the nozzle ejecting the water, and a bandwidth from 2MHz to 400MHz is claimed. If you work with RF you will probably wince at the sight of salt water coming near the RF connector, as we did.
The advantage of the system is that it allows antennas of multiple frequencies to be created at very short notice and using very little space or weight when not in use. The creator of the antenna at the US Navy’s SPAWAR technology organization points to its obvious application on Navy warships. Whether or not the sailors are using these antennas now isn’t clear, but one thing’s for certain, the idea hasn’t gone away. Early last year Popular Mechanics reported on a similar project under way courtesy of Mitsubishi, in Japan.