Review: Mini AMG8833 Thermal Camera

August 12, 2021 by Jenny List 29 Comments

In our ceaseless quest to bring you the best from the cheaper end of the global electronics markets, there are sometimes gadgets that we keep an eye on for a while because when they appear they’re just a little bit too pricey to consider cheap.

Today’s subject is just such a device, it’s a minimalist infra-red camera using the 8 pixel by 8 pixel Panasonic AMG8833 thermal sensor. This part has been around for a while, but even though any camera using it has orders of magnitude less performance than more accomplished models it has remained a little too expensive for a casual purchase. Indeed, these mini cameras were somewhere above £50 ($70) when they first came to our attention, but have now dropped to the point at which they can be found for somewhere over £30 ($42). Thirty quid is cheap enough for a punt on a thermal camera, so off went the order to China and the expected grey parcel duly arrived.

The interface on this camera is about as simple as it gets.

It’s a little unit, 40 mm x 35 mm x 18 mm, constructed of two laser-cut pieces of black plastic held together by brass stand-offs that hold a PCB between them, and on the front is a cut-out for the sensor while on the rear is one for the 35mm OLED display.At the side on the PCB is a micro USB socket which serves only as a power supply. It’s fair to say that this is a tiny unit.

Applying power from a USB battery bank, the screen comes up with a square colour thermal picture and a colour to temperature calibration stripe to its left. The colours adapt to the range of temperatures visible to the sensor, and there is a crosshair in the centre of the picture for which the temperature in Celsius is displayed below the picture. It’s a very straightforward and intuitive interface that requires no instruction, which is handy because the device has none. Continue reading “Review: Mini AMG8833 Thermal Camera” →

Should You Be Able To Repair It? We Think So.

August 11, 2021 by Jenny List 179 Comments

You own it, you should be able to fix it. So much equipment on sale today has either been designed to be impossible to maintain, unnecessarily too complex to maintain, maintainable only with specialist tooling only available to authorised service agents, or with no repair parts availability. It’s a hot-button issue in an age when sustainability is a global concern, so legislators and regulators worldwide now finally have it in their sights after years of inaction and it’s become a buzzword. But what exactly is the right to repair, and what do we want it to be?

Is It Designed For Repair?

A Nestle Dolce Gusto machine — For some reason, pod coffee makers are especially resistant to repair. Andy1982, CC BY 3.0

The first question to consider is this: does it matter whether or not you have the right to repair something, if it’s designed specifically with lack of repairability in mind? Consider a typical domestic pod coffeemaker such as a Tassimo or similar: despite being physically quite a simple device, it is designed to be especially complex to dismantle and reassemble. You just can’t get into it when something goes wrong.

Should it be the preserve of regulators to require design for easy repair? We think so. There are other forces working on the designers of home appliances; design-for-manufacture considerations and exterior appearance concerns directly affect the firm’s bottom line, while the end users’ repair experience is often at the bottom of the list, even though the benefit at a national level is obvious. That’s what laws are for.
Continue reading “Should You Be Able To Repair It? We Think So.” →

So You Can Solder Small SMD Devices. The Question Is, Just How Small?

August 9, 2021 by Jenny List 15 Comments

A highlight of last year’s Hackaday Remoticon was a soldering competition that had teams from around the world came together online and did the well-known MakersBox SMD Challenge kit in which a series of LED circuits of decreasing size must be soldered. The Hackaday crew acquitted themselves well, and though an 01005 resistor and LED certainly pushes a writer’s soldering skills to the limit it’s very satisfying to see it working. Lest that kit become too easy, [Arthur Benemann] has come up with something even more fiendish; his uSMD is a 555 LED flasher that uses a BGA 555 and a selection of 008004 small components.

The trick with an 01005 is to heat not the tinned and fluxed solder joint, but the trace leading up to it. If components of that size can be mastered then perhaps an 008004 isn’t that much smaller so maybe the same technique might work for them too. In his tip email to us he wrote “Soldering 008004 isn’t much worse than a 0201, you just need magnification“, and while we think he might be trolling us slightly we can see there’s no reason why it shouldn’t be do-able. Sadly he doesn’t seem to have made it available for us to buy and try so if you want to prove yourself with a soldering iron you’ll have to source the PCBs and parts yourself. Still, we suspect that if you are the type of person who can solder an 008004 then that will hardly be an onerous task for you.

Meanwhile this isn’t the first soldering challenge kit we’ve brought you, and of course if you’d like to hone your skills you can find the MakersBox one on Tindie.

ReactOS Is Going Places, With More Stable AMD64, SMP, And Multi-Monitor Support

August 8, 2021 by Jenny List 54 Comments

In the crowd of GNU/Linux and BSD users that throng our community, it’s easy to forget that those two families are not the only games in the open-source operating system town. One we’ve casually kept an eye on for years is ReactOS, the long-running open-source Windows-compatible operating system that is doing its best to reach a stable Windows XP-like experience. Their most recent update has a few significant advances mentioned in it that hold the promise of it moving from curiosity to contender, so is definitely worth a second look.

ReactOS has had 64-bit builds for a long time now, but it appears they’ve made some strides in both making them a lot more stable, and moving away from the MSVC compiler to GCC. Sadly this doesn’t seem to mean that this now does the job of a 64-bit Windows API, but it should at least take advantage internally of the 64-bit processors. In addition they have updated their support for the Intel APIC that is paving the way for ongoing work on multiprocessor support where their previous APIC driver couldn’t escape the single processor constraint of an original Intel 8259.

Aside from these its new-found support for multiple monitors should delight more productive users, and its improved support for ISA plug-and-play cards will be of interest to retro enthusiasts.

We took a close look at the current ReactOS release when it came out last year, and concluded that its niche lay in becoming a supported and secure replacement for the many legacy Windows XP machines that are still hanging on years after that OS faded away. We look forward to these and other enhancements in their next release, which can’t be far away.

The Magnetosphere Has A Ton Of Energy. Can A Guitar Amp Company Tap Into It?

August 7, 2021 by Jenny List 55 Comments

Researching a piece on vacuum tubes, we stumbled on something unexpected from Electro-Harmonix, best known for guitar amplifiers and audio tube manufacture. In a break from their core business, they plan to tap energy from the magnetosphere. This came as something of a surprise to their guitarist customers who were no doubt expecting a fancy new effects pedal, but it seems they’re serious.

The magnetosphere is the region of space surrounding the earth in which the earth’s magnetic field has most influence, and unlike the tidy pattern of magnetic field surrounding a bar magnet that you might have seen with iron filings at school, it’s distorted by the constant buffeting of the solar wind. This means that a significant quantity of potential energy is stored in its compression, and it’s this energy that Electro-Harmonix have their eye on.

Like Fox Mulder: we want to believe. Unfortunately the trouble with such ideas is readily visible with a quick web search; they attract a significant number of what one might charitably call cranks, and there is no shortage of unsubstantiated claims surrounding conspiracy theories, silenced genus inventors, and their mystery devices. Weird and wonderful descriptions and cryptic circuit diagrams abound, so separating the wheat if there is any from the inevitable chaff becomes a challenge. We respect that the Electro-Harmonix team are professional engineers who we hope are unlikely to become caught up in the weirder part of the Internet, but we’ll reserve our judgement until they provide more technical details of what they propose.

Header: NASA, Public domain.

MULTICS Gets A New Release… 52 Years After Launch

August 7, 2021 by Jenny List 27 Comments

If you have ever read anything about the history of UNIX, you may remember that its early development was influenced by an older operating system. MULTICS was developed in the 1960s by MIT and General Electric as a commercial operating system, and had been the system which UNIX writers [Thompson] and [Ritchie] had used. It became a Honeywell product, and the source code for its final commercial version was eventually released to the public. Has it become a dusty relic of interest only to historians? Seemingly not, because a new version has been released. It’s intended for us on the dps8m Honeywell mainframe simulator rather than physical hardware, so perhaps while it’s not such a dusty relic it remains something only for the enthusiast.

We won’t pretend to be experts on the architectures of 1960s mainframe operating systems, but it’s interesting to read for a moment about what it was in MULTICS that caused UNIX to be written. For something described by [Ken Thompson] as “Close to unusable”, with a fresh release in its 52nd year it isn’t doing badly.

We’ve traced the UNIX story in the past, without realising that MULTICS never entirely went away. Shame on us for the omission!

[Via Hacker News]

A Trio Of Photodiodes Make A Radiation Detector

August 6, 2021 by Jenny List 44 Comments

The instinctive reaction when measuring nuclear radiation is to think of a Geiger counter, as the low-pressure gas tube detectors have entered our popular culture through the Cold War. A G-M tube is not the only game in town though, and even the humble photodiode can be pressed into service. [Robert] gives us a good example, with a self-contained radiation detector head that uses a trio of BPW34s to do the job.

At its heart is a transimpedance amplifier, a not-often-seen op-amp configuration that serves as a very high gain current-to-voltage converter. This produces a spike for every radiation event detected by the diodes, which is fed to a comparator to produce a logic pulse. The diodes require a significant bias voltage, for which he’s used 48 V from a stack of 12 V photographic dry cells rather than a boost converter or other potentially noisy power supply. Such a sensitive high-gain device needs to be appropriately shielded, so the whole circuit is contained in a diecast box with a foil window to allow radiation to reach the diodes.

This isn’t the first BPW34-based radiation detector we’ve seen, so perhaps before looking for a Cold War era relic for our radiation experiments we should be looking in a semiconductor catalogue instead.