Nanovolt Meter Requires Careful Design For Accuracy’s Sake

May 17, 2022 by 25 Comments

Measuring voltages is fairly straightforward most of the time. Simply grab any old cheap multimeter, hook up the probes, and read off the answer. If, however, you need to measure very tiny voltages, the problem gets more complex. [Jaromir-Sukuba] designed a nanovoltmeter specifically to deal with this difficult case.

The nanovoltmeter is exactly what it sounds like: a voltmeter that is sensitive and stable enough to measure and report voltages on the scale of nanovolts. Having a tool that can do this reliably can be very useful when it comes to measuring very small resistances or working with ever-so-slight differential voltages. Continue reading “Nanovolt Meter Requires Careful Design For Accuracy’s Sake” →

When Hams Helped Polar Researchers Come In From The Cold

May 17, 2022 by 26 Comments

We always enjoy [The History Guy] videos, although many of them aren’t much about technology. However, when he does cover tech topics, he does it well and his recent video on how ham radio operators assisted in operation Deep Freeze is a great example. You can watch the video, below.

The backdrop is the International Geophysical Year (IGY) where many nations cooperated to learn more about the Earth. In particular, from 1957 to 1958 there was a push to learn more about the last unexplored corner of our planet: Antarctica. Several of the permanent bases on the icy continent today were started during the IGY.

It’s hard for modern audiences to appreciate what the state of personal communication was in 1957. There were no cell phones and if you are thinking about satellites, don’t forget that Sputnik didn’t launch until late 1957, so that wasn’t going to happen, either.

Operation Deep Freeze had ten U. S. Navy vessels that brought scientists, planes, and Seabees (slang for members of the Naval Construction Batallion) — about 1,800 people in all over several years culminating in the IGY. Of course, the Navy had radio capabilities, but it wasn’t like the Navy to let you just call home to chat. Not to mention, a little more than 100 people were left for each winter and the Navy ships went home. That’s where ham radio operators came in.

Hams would do what is called a phone patch for the people stationed in Antarctica. Some hams also send radiograms to and from the crew’s families. One teen named Jules was especially dedicated to making connections to Antarctica. We can’t verify it, but one commenter says that Jules was so instrumental in connecting his father in Antarctica to his fiancee that when his parents married, Jules was their best man.

Jules and his brother dedicated themselves to keeping a morale pipeline from New Jersey to the frozen stations. He figures prominently in recollections of many of the written accounts from people who wintered at the nascent bases. Apparently, many of the men even traveled to New Jersey later to visit Jules. What happened to him? Watch the end of the video and you’ll find out.

While being a ham today doesn’t offer this kind of excitement, hams still contribute to science. Want to get in on the action? [Dan Maloney] can tell you how to get started on the cheap.

Continue reading “When Hams Helped Polar Researchers Come In From The Cold” →

Kindle, EPUB, And Amazon’s Love Of Reinventing Wheels

May 17, 2022 by 48 Comments

Last last month, a post from the relatively obscure Good e-Reader claimed that Amazon would finally allow the Kindle to read EPUB files. The story was picked up by all the major tech sites, and for a time, there was much rejoicing. After all, it was a feature that owners have been asking for since the Kindle was first released in 2007. But rather than supporting the open eBook format, Amazon had always insisted in coming up with their own proprietary formats to use on their readers. Accordingly, many users have turned to third party programs which can reliably convert their personal libraries over to whatever Amazon format their particular Kindle is most compatible with.

Native support for EPUB would make using the Kindle a lot less of a hassle for many folks, but alas, it was not to be. It wasn’t long before the original post was updated to clarify that Amazon had simply added support for EPUB to their Send to Kindle service. Granted this is still an improvement, as it represents a relatively low-effort way to get the open format files on your personal device; but in sending the files through the service they would be converted to Amazon’s KF8/AZW3 format, the result of which may not always be what you expected. At the same time the Send to Kindle documentation noted that support for AZW and MOBI files would be removed later on this year, as the older formats weren’t compatible with all the features of the latest Kindle models.

If you think this is a lot of unnecessary confusion just to get plain-text files to display on the world’s most popular ereader, you aren’t alone. Users shouldn’t have to wade through an alphabet soup of oddball file formats when there’s already an accepted industry standard in EPUB. But given that it’s the reality when using one of Amazon’s readers, this seems a good a time as any for a brief rundown of the different ebook formats, and a look at how we got into this mess in the first place.

Continue reading “Kindle, EPUB, And Amazon’s Love Of Reinventing Wheels” →

A modified Palm IIIc mainboard

LED Backlight Brings Vibrant Colors To Classic Palm PDAs

May 17, 2022 by 10 Comments

Back in the days before the widespread adoption of smartphones, Palm was the market leader in PDAs. If you had one of those you’ll probably remember taking notes by writing those funky “Graffiti” characters and tapping your stylus onto, usually, a green monochrome screen. Some models even came with a battery-hungry backlight, but for the ultimate display experience you had to buy the Palm IIIc that came with a backlit full-colour display.

While revolutionary for its time, it was hampered by the technology available: the CCFL backlight took a second to start up, and even with the screen at full brightness it was rather dim by today’s standards. [TobleMiner] fixed these issues by designing a module to retrofit an LED backlight into your Palm IIIc.

A Palm IIIc showing the main menu on its displayThe new backlight consists of a long, thin PCB designed to fit exactly where the CCFL tube sits. The PCB holds twenty-one white LEDs along with their current-limiting resistors to provide even illumination from top to bottom. A little MOSFET soldered onto the mainboard ensures the new backlight also correctly responds to the device’s “brightness” setting. [TobleMiner] recommends to remove the bulky CCFL transformer from the Palm’s mainboard to disable the corresponding circuitry and save a bit of weight.

The end result is understandably hard to capture on camera, but apparently gives the screen more vibrant colours. In any case, this might be a useful hack for anyone with a Palm IIIc with a broken backlight, though we can’t remember if that was a common issue. If you’re among those who still use original Palm devices, you might like this Palm-compatible Bluetooth keyboard. Don’t have a classic PDA? You can also run PalmOS on modern custom hardware.

Things Are Getting Rusty In Kernel Land

May 17, 2022 by 163 Comments

There is gathering momentum around the idea of adding Rust to the Linux kernel. Why exactly is that a big deal, and what does this mean for the rest of us? The Linux kernel has been just C and assembly for its entire lifetime. A big project like the kernel has a great deal of shared tooling around making its languages work, so adding another one is quite an undertaking. There’s also the project culture developed around the language choice. So why exactly are the grey-beards of kernel development even entertaining the idea of adding Rust? To answer in a single line, it’s because C was designed in 1971, to run on the minicomputers at Bell Labs. If you want to shoot yourself in the foot, C will hand you the loaded firearm.

On the other hand, if you want to write a kernel, C is a great language for doing low-level coding. Direct memory access? Yep. Inline assembly? Sure. Runs directly on the metal, with no garbage collection or virtual machines in the way? Absolutely. But all the things that make C great for kernel programming also make C dangerous for kernel programming.

Now I hear your collective keyboards clacking in consternation: “It’s possible to write safe C code!” Yes, yes it is possible. It’s just very easy to mess up, and when you mess up in a kernel, you have security vulnerabilities. There’s also some things that are objectively terrible about C, like undefined behavior. C compilers do their best to do the right thing with cursed code like i++ + i++; or a[i] = i++;. But that’s almost certainly not going to do what you want it to, and even worse, it may sometimes do the right thing.

Rust seems to be gaining popularity. There are some ambitious projects out there, like rewriting coreutils in Rust. Many other standard applications are getting a Rust rewrite. It’s fairly inevitable that the collection of Rust developers started to ask, could we invade the kernel next? This was pitched for a Linux Plumbers Conference, and the mailing list response was cautiously optimistic. If Rust could be added without breaking things, and without losing the very things that makes Rust useful, then yes it would be interesting. Continue reading “Things Are Getting Rusty In Kernel Land” →

Transparent Framedeck Is Clearly Capable

May 17, 2022 by 15 Comments

When the universe tells you to build a cyberdeck, then build a cyberdeck you must. The lucky [Richard Sutherland] got an email from user-serviceable laptop purveyors Framework about the availability of their main board for use as a single-board computer. They agreed to send him a laptop and some extra modules as long as he promised to build something awesome with it. There was just one fabulous caveat: whatever design he came up with had to be released to the public.

[Richard] took this capable board with four USB ports and built an all-in-one that pays homage to the slab-style computers like the TRS-80 Model 100, which [Richard] really wanted as a kid. It looks lovely in layered acrylic and brass, and even though we pretty much always think that see-through is the best design choice you can make, transparency really works here. Tucked into those layers is a custom 36-key split running on an Elite-C microcontroller with Gazzew Boba U4 Silent-but-tactile switches, and a trackball in between. Be sure to take the build tour and check out all the process pictures.

Acrylic looks great and seems great on paper, but what about actual use? [Richard] put rubbery SKUF feet on the front, and a pair of repositionable feet on the back. Not only will it stay in place on the table, but he’ll be able to see the screen better and type at an angle greater than zero.

As cool as it would be to have Framedeck in the apocalypse, it will be hard to hide and could get looted. You might want to build something a bit more concealed.

Building Petahertz Logic With Lasers And Graphene

May 17, 2022 by 19 Comments

There was a time when we thought a 50 MHz 486 was something to get excited about. In comparison, the computer this post was written on clocks in at about 3.8 GHz, which these days, isn’t an especially fast machine. But researchers at the University of Rochester and the  Friedrich-Alexander-Universität Erlangen-Nürnberg want to blow the doors off even the fastest modern CPUs. By using precise lasers and graphene, they are developing logic that can operate at nearly 1 petahertz (that’s 1,000,000 GHz).

These logic gates use a pair of very short-burst lasers to excite electrical current in graphene and gold junctions. Illuminating the junctions very briefly creates charge carriers formed by electrons excited by the laser. These carriers continue to move after the laser pulse is gone. However, there are also virtual charge carriers that appear during the pulse and then disappear after. Together, these carriers induce a current in the graphene. More importantly, altering the laser allows you to control the direction and relative composition of the carriers. That is, they can create a current of one type or the other or a combination of both.

This is the key to creating logic gates. By controlling the real and virtual currents they can be made to add together or cancel each other out. You can imagine that two inputs that cancel each other out would be a sort of NAND gate. Signals that add could be an OR or AND gate depending on the output threshold.

[Ignacio Franco], the lead researcher, started working on this problem in 2007 when he started thinking about generating electrical currents with lasers. It would be 2013 before experiments bore out his plan and now it appears that the technique can be used to make super fast logic gates.

We often pretend our logic circuits don’t have any propagation delays even though they do. If you could measure it in femtoseconds, maybe that’s finally practical. Then again, sometimes delays are useful. You have to wonder how much the scope will cost that can work on this stuff.