Billet Machining A Special Xbox

September 15, 2022 by Jenny List 12 Comments

The world of console modding has delivered us some amazing projects over the years, usually rendering an original into a completely different form factor. [Modified] has done a special bit of console modding on an Xbox Series X, with the unusual result of keeping exactly the same form factor. What makes it special? His Series X has been given a new case, almost identical to the original, but instead of molded plastic it’s machined entirely from a single billet of aluminium stock.

From one perspective it’s a slightly crazy endeavor — pushing the limits of his mill to remove 90% of the stock. But from another it’s an interesting tale of how to approach such a project, of the challenges in reaching further into a workpiece than the tooling is designed for, and also of the cooling for the Xbox itself. Sure he could have made it from aluminium plate and screwed it together, but in doing so he’d have denied us the chance to follow a machining adventure.

The result is an Xbox that’s nominally the same as when it left the factory, but which looks so much cooler. Oddly the aluminum doesn’t act as a heatsink because the console is air-cooled, but particularly on the bottom there are more holes than were found in the original. On the front is an engraving of Master Chief from Halo 2‘s cover art which really puts the finishing touch on the build — though we wonder whether it might benefit from a little resin to make it stand out a bit.

Hungry for more Series X case mods? They don’t come bigger than this one!

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How The BBC (Still) Sends Audio To Transmitter Sites

September 13, 2022 by Jenny List 25 Comments

Running a radio station is, on the face of it, a straightforward technical challenge. Build a studio, hook it up to a transmitter, and you’re good to go. But what happens when your station is not a single Rebel Radio-style hilltop installation, but a national chain of transmitter sites fed from a variety of city-based studios? This is the problem facing the BBC with their national UK FM transmitter chain, and since the 1980s it has been fed by a series of NICAM digital data streams. We mentioned back in 2016 how the ageing equipment had been replaced with a modern FPGA-based implementation without any listeners noticing, and now thanks to [Matt Millman], we have a chance to see a teardown of the original 1980s units. The tech is relatively easy to understand from a 2020s perspective, but it still contains a few surprises.

In each studio or transmitter site would have been a 19″ rack containing one of these units — a card frame with a collection of encoder or decoder cards. These are all custom-made by the BBC’s engineering department to a very high standard, and use period parts such as the familiar Z80 microprocessor and some Philips digital audio chips, which followers of high-end consumer audio may recognize. As you’d expect for a mission critical device, many of the functions are duplicated for redundancy, with their outputs compared to give warning of failures.

The surprise comes in the NICAM encoder and decoder — it’s a custom LSI chip made exclusively for the BBC. This indicates the budget available to the national broadcaster, and given that these units have in some cases been working for over 35 years, we’re guessing that the license payers got their money’s worth.

You can read about the original switch-over in 2016, and a little more about NICAM, too.

Inexpensive Reading Glasses Become Stereoscope

September 13, 2022 by Jenny List 17 Comments

It’s an unfortunate consequence of growing older, that no longer are you able to read the print on a SOT-23 package or solder a QFN without magnification. Your eyes inexorably start to fail, and to have any hope of continuing a set of reading glasses is required. We have this in common with [Niklas Roy], who noticed while shopping for cheap reading glasses that their lenses were of surprisingly good quality. The result of this observation was a stereoscope made from card and a few euros worth of eyewear.

In the tradition of [Niklas]’ work it has a high level of attention to detail, which manifests itself here in a parametric web-based template generator to produce a result tailored to your glasses. It’s a fairly straightforward trapezoid shape, with a compound lens made from two sets of glasses drilled and held back-to-back with zip ties.

It served as a project for a group of children, and of course because stereo cameras are a relative rarity he also investigated taking his own pictures by moving a smartphone for left and right eye perspectives. It seems the youngsters had a lot of fun.

These lenses hadn’t come up on our radar until now, but like many goodies in a dollar store they’re certainly something to take a look at. Maybe not as a stereoscope for everyone though, some of us can’t see what the fuss is about.

Equalize Your Listening With HiFiScan

September 12, 2022 by Jenny List 28 Comments

Audiophiles will go to such extents to optimize the quality of their audio chain that they sometimes defy parody. But even though the law of diminishing returns eventually becomes a factor there is something in maintaining a good set of equipment. But what if your audio gear is a little flawed, can you fix it electronically? Enter HiFiScan, a piece of Python software to analyse audio performance by emitting a range of frequencies and measuring the result with a microphone.

This is hardly a new technique, and it’s one which PA engineers have used for a long time to tune out feedback resonances, but an easy tool bringing it to the domestic arena is well worth a look. HiFiScan is a measuring tool so it won’t magically correct any imperfections in your system, however it can export data in a format suitable for digital effects packages.

Naturally its utility is dependent on the quality of the hardware it’s used with, but the decent quality USB microphone used in the examples seems to give good enough results. We see it used in a variety of situations, of which perhaps the most surprising is a set of headphones that have completely different characteristics via Bluetooth as when wired.

If audio engineering interests you, remember we have an ongoing series: Know Audio.

The Hunt For A Rare Version Of IBM’s OS/2

September 12, 2022 by Jenny List 40 Comments

Slovenian OS/2 Warp 4 was a popular OS choice in that European country back in the day, but could the Slovenian Computer Museum lay their hands on a copy? In that question lies a bit of detective work and some luck.

There’s an old gag, about how this is finally the year of the Linux desktop. But oddly back in the ’90s it almost seemed possible, because alongside Microsoft Windows there were a host of other players that just might have become challengers. Foremost among them was IBM’s OS/2, a desktop PC operating system that could very much give Windows a run for its money. It could even run 16-bit Windows applications thanks to the code-sharing deal between the two companies dating back to the DOS days. Big Blue were so anxious to take their OS into new markets that they localized it into languages which Microsoft hadn’t touched, of which Slovenian was one.

But a couple of decades later, could a copy of this rare operating system version be found? While it may still lurk on a dusty shelf in an IT office somewhere it’s proved elusive, and online sources have dried up. The quest for it makes interesting reading for anyone with an interest in that period of retrocomputing, and finally ended up at the Slovenian company which had performed the localisation. This resulted in a copy of the OS, but not of the media, box, or paperwork. It yielded the fascinating discovery that IBM had localized the Windows 3.1-derived components as well as their own code, something that Microsoft had never done.

So do you have a boxed Slovenian OS/2 Warp 4 on a dusty shelf? Someone at the Slovenian Computer History Museum might like to see it. Meanwhile it’s a surprise to find that OS/2 is still supported.

Finally We Can Watch The Deere Cracking Def Con Talk

September 12, 2022 by Jenny List 12 Comments

A few weeks ago, some tantalizing social media posts emerged from a Def Con talk, in which [Sick Codes] broke into the screen control unit for a John Deere tractor live on stage, and proceeded to play a special Deere-themed DOOM level upon it. At the time there was nothing more to go on, but we’re pleased to find out that the whole talk has been put online.

The talk starts with an introduction to the topic, to the basics of the control units within the machine and to the various different ages of Deere screen unit. We find that the earlier machines, which are still at work on farms worldwide, rely on outdated Windows CE versions, though the very latest screens run a Linux variant.

It’s one of these last screens to which he turns his attention, and we’re treated to an in-depth look at some of its secrets. After a lot of dead ends and learning exercises the final result is distilled into a pogo pin adapter for the hardware part, and a simple enough cron job to bypass one of Deere’s defenses by keeping the filesystem writable so a file can be updated. There’s a bit more detail about the special DOOM level too, as a special bonus.

You can see our original mention of this talk, or read some of our past Deere coverage.

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London Bridge Has Fallen — By Radio

September 10, 2022 by Jenny List 25 Comments

One of the global news stories this week has been the passing of the British monarch, Queen Elizabeth II. Since she had recently celebrated 70 years on the throne, the changing of a monarch is not something that the majority of those alive in 2022 will have seen. But it’s well known that there are a whole suite of “London Bridge has fallen” protocols in place for that eventuality which the various arms of the British government would have put in motion immediately upon news from Balmoral Castle. When it became obvious that the Queen’s health was declining, [Hackerfantastic] took to the airwaves to spot any radio signature of these plans. [Update 2022-09-11] See the comments below and a fresh Tweet to clarify, it appears these were not the signals they were at first suspected to be.

What he found in a waterfall view of the 4 MHz military band was an unusual transmission, a set of strong QPSK packets that started around 13:40pm on the 8th of September, and continued on for 12 hours before disappearing. The interesting thing about these transmissions is not that they were a special system for announcing the death of a monarch, but that they present a rare chance to see one of the country’s Cold War era military alert systems in action.

It’s likely that overseas embassies and naval ships would have been the intended recipients and the contents would have been official orders to enact those protocols, though we’d be curious to know whether 2022-era Internet and broadcast media had tipped them off beforehand that something was about to happen. It serves as a reminder: next time world news stories happen in your part of the world, look at the airwaves!