Retrotechtacular: 934 MHz CB Radio

November 21, 2019 by Jenny List 49 Comments

The radio spectrum is carefully regulated and divided up by Governments worldwide. Some of it is shared across jurisdictions under the terms of international treaties, while other allocations exist only in individual countries. Often these can contain some surprising oddities, and one of these is our subject today. Did you know that the UK’s first legal CB radio channels included a set in the UHF range, at 934 MHz? Don’t worry, neither did most Brits. Behind it lies a tale of bureaucracy, and of a bungled attempt to create an industry around a barely usable product.

Hey, 2019, Got Your Ears On?

Did this car make you want a CB radio? Stuurm [CC BY-SA 3.0]

Mention CB radio in 2019 it’s likely that the image conjured in the mind of the listener will be one from a previous decade. Burt Reynolds and Jerry Reed in Smokey and the Bandit perhaps, or C. W. McCall’s Convoy. It may not be very cool in the age of WhatsApp, but in the 1970s a CB rig was the last word in fashionable auto accessories and a serious object of desire into which otherwise sane adults yearned to speak the slang of the long-haul trucker.

If you weren’t American though, CB could be a risky business. Much of the rest of the world didn’t have a legal CB allocation, and correspondingly didn’t have access to legal CB rigs. The bombardment of CB references in exported American culture created a huge demand for CB though, and for British would-be CBers that was satisfied by illegally imported American equipment. A vibrant community erupted around UK illegal 27 MHz AM CB in the late 1970s, and Government anger was met with campaigning for a legal allocation. Brits eventually got a legal 27 MHz allocation in November 1981, but the years leading up to that produced a few surprises.

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There’s More To Designing A PCB Business Card Than Meets The Eye

November 19, 2019 by Jenny List 9 Comments

A curious custom that survives from the pre-computer era is that of the business card. If you walk the halls at a trade event you’ll come a way with a stack of these, each bearing the contact details of someone you’ve encountered, and each in a world of social media and online contact destined to languish in some dusty corner of your desk. In the 21st century, when electronic contacts harvested by a mobile phone have the sticking power, how can a piece of card with its roots in a bygone era hope to compete?

It’s a question [Anthony Kouttron] has addressed in the design of his thoroughly modern business card, and along the way he’s treated us to an interesting narrative on how to make the card both useful beyond mere contact details as well as delivering that electronic contact. The resulting card has an array of rulers and footprints as an electronic designer’s aid, as well as an NFC antenna and chip that lights an LED and delivers his website address when scanned. There are some small compromises such as PCB pads under the NFC antenna, but as he explains in the video below, they aren’t enough to stop it working. He’s put his work in a GitHub repository, should you wish to do something similar.

There’s a rich vein of business card projects on these pages, but so far surprisingly few are NFC equipped. That didn’t stop someone from making an NFC-enabled card with user interaction though.

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Add A Bit Of PCB Badge Glamour To Your Boring ID Badge

November 18, 2019 by Jenny List 6 Comments

When we talk about badges and printed circuit boards, it is usually in the context of the infinite creativity of the Badgelife scene, our community’s own art form of electronic conference badges. It’s easy to forget when homing in on those badges that there are other types of badge, and thus [Saimon]’s PCB badge holder is an entertaining deviation from our norm. His workplace requires employees to carry their credit-card-sized ID pass with them at all times, but the plastic holder that came with his had broken. So he did what any self-respecting engineer would do, and designed his own holder using PCBs.

It’s a three-way sandwich with identical front and back PCBs featuring a nice design, but the clever bit is the middle PCB. It is U-shaped to slide the card in from the side, but to retain the card it has a couple of springy milled PCB arms each with a small retaining tooth on the end. This is an ingenious solution, with just enough give to bend, but not so much as to break.

The three boards are glued together, it seems his original aim was to reflow solder them but this was not successful. The result is an attractive and functional badge holder, which if Hackaday required us to have a corporate ID you can be sure we’d be eyeing up for ourselves.

UNIX Version 0, Running On A PDP-7, In 2019

November 17, 2019 by Jenny List 34 Comments

WIth the 50th birthday of the UNIX operating system being in the news of late, there has been a bit of a spotlight shone upon its earliest origins. At the Living Computers museum in Seattle though they’ve gone well beyond a bit of historical inquiry though, because they’ve had UNIX (or should we in this context say unix instead?) version 0 running on a DEC PDP-7 minicomputer. This primordial version on the original hardware is all the more remarkable because unlike its younger siblings very few PDP-7s have survived.

The machine running UNIX version 0 belongs to [Fred Yearian], a former Boeing engineer who bought his machine from the company’s surplus channel at the end of the 1970s. He restored it to working order and it sat in his basement for decades, while the vintage computing world labored under the impression that including the museum’s existing machine only four had survived — of which only one worked. [Fred’s] unexpected appearance with a potentially working fifth machine, therefore, came as something of a surprise.

To load the OS a disk emulator was connected to the machine, and for possibly the first time in many decades a new UNIX version 0 device driver was written to enable it to be used. The first login was the user “dmr”, a homage to UNIX co-creator Dennis M. Ritchie.

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The ESP32, Laid Bare

November 17, 2019 by Jenny List 31 Comments

Most readers will be familiar with the ESP32, Espressif’s dual-core processor with integrated WiFi and Bluetooth. Few of us though will have explored all of its features, including its built-in encryption facilities and secure booting capability. With these, a developer can protect and secure their code, and keep their devices secure.

That sense of security may now be illusory though, thanks to [LimitedResults] who has developed a series of attacks on the chip that compromise its crypto core, secure boot, and flash encryption. This enables both the chance of arbitrary code execution and firmware extraction on locked-down ESP32 devices.

To achieve all this he used a glitching technique on the device’s power supply, inserting a carefully timed glitch in the rail to coincide with a particular instruction being executed. For those of us who are not experts in this technique, he provides a basic primer with a description of his home-made glitcher made using a CMOS switch chip.

It appears that there is no solution to this attack short of new silicon, however, it should be borne in mind that it’s something that depends upon a specialist hacker with a well-equipped bench, and is thus only likely to be a significant headache to manufacturers. But it undermines a key feature of a major line of microcontrollers, and as such it remains a significant piece of work.

The Ultimate Hacker’s Compact 4WD!

November 16, 2019 by Jenny List 3 Comments

If you’ve spent any time at one of the larger European hacker camps over the last few years you’ll have seen the invasion of little electric vehicles sporting hoverboard motors as an all-in-one propulsion system. German hackers, in particular, have incorporated them into the iconic Bobby Car children’s toy, and ca be seen whizzing around looking slightly incongruous as adults perched on transport designed for five-year-olds.

[Peter Pötzi] has created just such an electric Bobby Car, and his one is particularly well-executed with a 3D-printed steering column extender and four motors for full 4WD rather than the usual two. A steering wheel-mounted display has a neat enclosure, and is fed SPI from the ESP32 that runs the show via an RJ45 patch cable. Many of these builds use hoverboard motor controllers with hacked firmware, but this one instead takes a set of off-the-shelf VESCs. Control comes via a set of Xbox 360 trigger buttons mounted to the underside of the steering wheel.

The result is typically self-contained as are all the Bobby Car builds, with the added bonus of the extra power of four motors rather than two. We’re not so sure that 4WD gives it off-road capabilities though, but having seen these vehicles perform some nifty maneuvers in the past perhaps it’ll lend extra traction on corners.

The Book Of Dreams Brings Back All Your Memories

November 16, 2019 by Jenny List 16 Comments

The retro-facing side of British social media has been abuzz for the last few days with a very neat piece of marketing form the catalogue retailer Argos: they’ve digitised all their catalogues since 1975 and put them online. While this contains a cross-section of over four decades’ styles, fads, and ephemera, it also gives the browser a fascinating look at a host of retrotechnology from a contemporary viewpoint rather than through the rose-tinted glasses of 2019. It may not be a hack, but we guarantee you’ll spend a while browsing it!

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