It is sometimes a surprise in our community of tinkerers, builders, hackers, and makers, to find that there are other communities doing very similar things to us within their own confines, but in isolation to ours. A good example are the modified vehicle crowd. In their world there are some epic build stories and the skills and tools they take for granted would not in any way be unfamiliar to most Hackaday readers.
As part of a discussion about electric vehicles near where this is being written, someone tossed an interesting link from that quarter into the mix; a two-part treatise on building ultra-light-weight tubular frame vehicles. Or space frames, as you might know them.
You might think that making a tubular framed for a vehicle would be a straightforward enough process, but as the article explains, it contains within it a huge well of geometry and metallurgy to avoid a creation that is neither too heavy nor contains excessive weakness. Part one deals mainly with prototyping a frame, the selection of materials and joining tubes, while part two goes into more detail on fabrication. The author likes brazing which may offend the sensibilities of welding enthusiasts, but you can substitute your jointing tech of choice.
A particularly neat suggestion, one of those simple ideas that make you wish you’d thought of it yourself, is to prototype a frame in miniature with copper wire and solder to evaluate the effect of different forces upon it before you commit your final design to steel.
The articles are a few years old, but no less pertinent in the information they contain. Meanwhile if you are a spaceframe veteran, then you may have your own suggestions for the comments below. And if you’d like some tips on how not to build a spaceframe, have a look at this motorcycle.
As the LoRa low-bandwidth networking technology in license-free spectrum has gained traction on the wave of IoT frenzy, LoRa networks have started to appear in all sorts of unexpected places. Sometimes they are open networks such as The Things Network, other times they are commercially available networks, and then, of course, there are entirely private LoRa installations.
If you are interested in using LoRa on a particular site, it’s an interesting exercise to find out what LoRa traffic already exists, and to that end [Joe Broxson] has put together a useful little device. Hardware wise it’s an Adafruit Cortex M0 Feather with onboard LoRa module, paired with a TFT FeatherWing for display, and software wise it scans a set of available frequencies and posts any packets it finds to the scrolling display. It also has the neat feature of logging packets in detail to an SD card for later analysis. The whole is enclosed in a 3D printed case from an Adafruit design and makes for a very attractive self-contained unit.
If you were a home constructor in the 8-bit era, the chances are that if you built a microcomputer system you would have ended up with a bare printed circuit board and a terminal. If you were on a budget you might have had a piece of stripboard as well, or maybe even wire-wrap. Beautiful cases were out of reach, they came with expensive commercial computers that were not the preserve of impoverished hobbyists.
Constructing an 8-bit machine in 2017 is a much easier process, there are many more options at your disposal. There is no need to make a bare PCB when you have a 3D printer, and this is demonstrated perfectly by [Dirk Grappendorf]’s 6502 computer project. He’s built from scratch an entire 6502 system, with a text LCD display, and housed it in a case with a keyboard that would put to shame all but the most expensive commercial machines from back in the day.
But this is more than just a hobby project thrown together that just happens to have a nice case, he’s gone the extra mile to the extent that this is professional enough that it could have been a product. If you’d been offered [Dirk]’s machine in 1980 alongside the competitors from Apple and Commodore, you’d certainly have given it some consideration.
We’ve seen retrocomputers too numerous to mention on these pages over the years, so if they are your thing perhaps it’s time to draw your attention to our VCF West reports, and to our reviews of computer museums in Germany, and Cambridge or Bletchley, UK.
[Seb Holzapfel, VK2SEB] has a rather nice spectrum analyser, a Hewlett Packard 141T. It’s an entirely analogue instrument though, so it lacks some of the sophisticated features you might expect to see on its modern counterparts.
One feature the HP does have is a vertical deflection output that in effect allows the trace to be reproduced on an oscilloscope. [Seb] has taken that and applied it to an STM32F746 Discovery board with its associated LCD touchscreen to produce an interface for the HP that includes modern features such as trace normalisation and a waterfall view. Along the way he’s had to make a voltage level converter to render the HP’s scan output into a range acceptable for the ST board.
He goes into detail on his software for the project, which he is at pains to remind us is still very much a work in progress. He notes that the HP has a range of other outputs (on those “D” sockets that include co-axial connectors) that provide information about its band and scan settings, so there is ample possibility for further customisation.
If you are interested in this project then the code is all available via GitHub, otherwise you can watch his video below the break. He’s labelled it as “Part 1”, so we look forward to more on this project.
What do you do when your keenly anticipated hacker camp releases details of its upcoming badge and you really want to have a go at coding for it, but there are no badges for you to try yet? If you are [Artdanion], this is not a problem, you simply build your own.
He found his requirement to interface with genuine hardware exceeded the abilities of the emulator that the SHACamp 2017 badge team had thoughtfully provided, so he reached for breakout boards for the ESP32, the MPR121 touch sensor, and the e-ink display, and assembled his own clone on a piece of stripboard. Not only did it provide him with enough to develop his own apps, he found when he brought it to the event that the public release of the official firmware ran on it with only a few configuration tweaks. He had an official event badge, that wasn’t the event badge. Is this the first time this has been done? We think it might be.
The home-made badge is an impressive piece of work, but it ties into an observation we made at the end of our review of the official version of the SHA2017 badge. The use of an ESP32 with well-designed peripherals and a solid firmware means that this is a design that is likely to form the bedrock upon which some future badges are built. [Artdanion] has proved how straightforward it is to clone, we’d like to be so bold as to make the prediction that we’ll see more developments of this platform at future events. Meanwhile this home-made badge is a neat achievement, and we can only imagine the surprise of the SHA2017 badge team on being presented with a clone of their work for reflashing.
If you sign up for a European hacker camp such as CCC Camp in Germany or SHA Camp in the Netherlands, you’ll see among the items recommended to take with you, a DECT handset. DECT, or Digital Enhanced Cordless Telecommunications, refers to the set of standards that lie behind the digital cordless telephones that are ubiquitous across Europe and some countries elsewhere in the world. These standards cover more than just the simple two-way telephone calls through a base station that most Europeans use them for though, they define a fully functional multi-cell 3G phone and data networking system. This means that an event like SHA Camp can run its own digital phone network without having to implement cell towers.
Olivetti promotional Net3 image
Reading the history of DECT, there is the interesting snippet that the first DECT product on the market in 1993 was not a telephone but a networking device, and incidentally the first wireless LAN product on the European market. Olivetti’s Net3 provided 512kB/s wireless networking to a base station with Ethernet or Token Ring interfaces for connection to a LAN. In its original form it was an internal card for a desktop PC coupled to a bulky external box containing radio circuitry and antenna, but its later incarnations included a PCMCIA card with a much smaller antenna box. The half-megabit speed seems tiny by today’s standards, but in the pre-multimedia world of 1993 would have been perfectly adequate for a Novell Netware fileserver and an HP Laserjet 4.
[Heinz Wolff] swallows a condom in another Olivetti promotional image.
Mystery Technology
So DECT is an interesting technology that can do more than just a simple cordless phone, and its first product was unexpectedly somewhat groundbreaking. It then becomes even more interesting to find that Net3 has left very little evidence of itself to find that can be found on the Web, and learning more about it requires a little detective work.
The Wikipedia entry has the bare bones, but it speaks volumes about the obscure nature of the product that the encyclopedia’s only picture of it is a tiny thumbnail-sized promotional image of the PCMCIA variant in a chunky mid-1990s laptop. A further search reveals a 1993 British Olivetti staff newsletter (PDF) carrying another promotional image of the desktop Net3 device featuring the then-well-known TV personality and academic [Heinz Wolff] demonstrating the technology bizarrely by swallowing a DECT medical instrumentation transponder wrapped in a condom. Some press releases remain in the fossilized remnants of the 1990s internet, and a Net3 design team member’s LinkedIn page led us to the patent covering the system, but that’s pretty much it. We can’t even find a high enough resolution image of a Net3 card for our featured image slot.
Wireless Things Before Their Time
It’s obvious that Net3 and DECT networking as a high-end wireless LAN before a need for wireless LANs existed never made it, but what is perhaps more interesting is that it seems to have left no legacy for other more mundane applications. We are in the midst of an explosion of hype around the Internet of Things and it seems new short-range wireless networking technologies appear almost daily, yet the world seems to have overlooked this robust, low power, and mature wireless network with its own dedicated frequency allocation that many of us already have in our homes. It seems particularly surprising that among the many DECT base stations on sale at your local consumer electronics store there are none with an Internet connection, and there is no market for IoT devices that use DECT as their backhaul.
In the open-source community there has been some work on DECT. The OsmocomDECT project for example provides a DECT software stack, and deDECTed.org states an aim to “better understand DECT and its security and to create an Open Source implementation of the DECT standard”. But there seems to have been very little hardware work in our community on the standard, for example there are no DECT-specific projects on Hackaday.io.
Net3 then was a product before its time, a herald of what was to come, from that twilight period when the Web was definitely a thing but had yet to become the world’s universal information repository. Public wireless networking was still several years in the future, so there was no imperative for road warriors to equip themselves with a Net3 card or for computer manufacturers — not even Olivetti themselves! — to incorporate the technology. It thus didn’t take the world by storm, and unusually for such a ground-breaking computer product there remains little legacy for it beyond a rarely-used feature of the protocol Europeans use for their cordless phones.
Did you have a Net3 card? Do you still have one? Let us know in the comments.
If you are an American, you’ll probably now find yourself in one of three camps. People who are going to see the upcoming solar eclipse that will traverse your continent, people who aren’t going to see the eclipse, and people who wish everyone would just stop going on incessantly about the damn eclipse.
Whichever of those groups you are in though, there is an interesting project that you can be a part of, an effort from the University of Massachusetts Boston to crowdsource scientific observation of the effect a solar eclipse will have on the upper atmosphere, and in particular upon the propagation of low-frequency radio waves. To do this they have been encouraging participants to build their own simple receiver and antenna, and make a series of recordings of the WWVB time signal station before, during, and after the eclipse traverse.
This is an interesting and unusual take upon participation in the eclipse, and has the potential to advance the understanding of atmospheric science. It would be fascinating to also look at the effect of the eclipse on WSPR contacts, though obviously those occur in amateur bands at higher frequencies.
If you are an EclipseMob participant, we’d love to hear from you in the comments. Does your receiver perform well?
The home-made badge is an impressive piece of work, but it ties into an observation we made at the end of 
