This CRT Luggable Makes Sense

There was a time when portable computing meant not a svelte laptop but a suitcase-sized machine that was really a slimmed-down desktop with a small CRT incorporated int he same box. They were heavy and unwieldy, but the computing compromises of using one at the time were less than with what served for more portable machinery. It’s a form factor which understandably has long ago disappeared, but that hasn’t stopped [Sdomi] from reviving it with a machine that packs plenty of modern computing power.

It’s a project that started with a monitor, a diminutive green-screen model which had previously adorned a CNC machine. It’s a composite model, so it’s driven from a VGA-to-composite converter. The computing power comes from a thin-client board that packs an up-to-date AMD Ryzen processor and 32 GB of memory, and the case is manufactured from oriented strand chipboard.

The result is a chunky but definitely practical and usable take on a portable cyberdeck, with the caveat that a composite monitor will not deliver the resolution some of us might be used to. We have to admit rather liking it, there’s nothing like the curved glass of a CRT.

It’s by no means the only up to date luggable we’ve seen, though more often now they feature an LCD.

Microelectrode (Utay) array and the decoding of the corresponding actions. (Francis R. Willet et al., 2023)

Restoring A Person’s Voice Using A Brain-Computer Interface

Being able to vocalize is one of the most essential elements of the human experience, with infants expected to start babbling their first words before they’re one year old, and much of their further life revolving around interacting with others using vocalizations involving varying degrees of vocabulary and fluency. This makes the impairment or loss of this ability difficult to devastating, as is the case with locked-in syndrome (LIS), amyotrophic lateral sclerosis (ALS) and similar conditions, where talking and vocalizing has or will become impossible.

In a number of concurrent studies, the use of a brain-computer interface (BCI) is investigated to help patients suffering from LIS (Sean L. Metzger et al., 2023) and ALS (Francis R. Willett et al., 2023) to regain their speaking voice. Using the surgically implanted microelectrode arrays (Utah arrays) electrical impulses pertaining to the patient’s muscles involved in speaking are recorded and mapped to phonemes, which are the elements that make up speech. Each of these phonemes requires a specific configuration of the muscles of the vocal tract (e.g. lips, tongue, jaw and larynx), which can be measured with a fair degree of accuracy. Continue reading “Restoring A Person’s Voice Using A Brain-Computer Interface”

Making An Injection Mold For Yourself

Injection molding is the obvious onward step from 3D printing when the making of a few plastic parts becomes their series manufacture. The problem with injection molding is though, that making a mold can be prohibitively expensive. Has the advent of affordable CNC machining changed that? [Teaching Tech] takes a look, and machines a mold for part of a bicycle bracket.

With a diversion into home-made silicone seals for the injection molding machine, he proceeds to machine the mold itself from a block of aluminium. It’s a basic introduction to mold construction for those of us who’ve never ventured in this direction before, and it provides some interesting lessons. As we’d expect he does a rough machining pass before returning with a ball-end tool to smooth off those curves, but there’s a lesson in measuring rather than believing the paperwork. The tool he used was a bit smaller then the spec, so his path left some rough edges that had to be returned to. Otherwise the use of a removable pair of bolts to form holes in the finished part is we guess obvious after watching the video, but it’s something we learned as injection molding newbies.

This video follows on from a previous one we also covered, in which we’re introduced to the machine itself.

Continue reading “Making An Injection Mold For Yourself”

Photography Goes Leaf Green

Something that haunts film photographers is the prospect of a film shortage. This won’t replace film in that event, but [Applied Science] demonstrates photography using leaves. That’s right, a plant can record an image on its leaves.

Anyone with a high-school level of education can tell you that the leaf is a solar energy harvester, with the green chlorophyll using CO2 scavenged from the air to make sugars in the presence of light. It stands to reason that this light sensitivity could be used to capture images, and indeed if you place a leaf in the dark for an extended period of time its chlorophyll fades away where there is no light. The technique described in the video below the break is different though, and much more sensitive than the days-long exposures required to strip chlorophyll. It relies on starch, which the leaf uses to store energy locally when it has an excess of light. Continue reading “Photography Goes Leaf Green”

The Device That Won WW2: A History Of The Cavity Magnetron

[Curious Droid] is back with a history lesson on one of the most important inventions of the 20th century: The cavity magnetron. Forged in the fighting of World War II, the cavity magnetron was the heart of radar signals used to identify attacking German forces.

The magnetron itself was truly an international effort, with scientists from many countries providing scientific advances. The real breakthrough came with the work of  [John Randall] and [Harry Boot], who produced the first working prototype of a cavity magnetron. The device was different than the patented klystron, or even earlier magnetron designs. The cavity magnetron uses physical cavities and a magnetic field to create microwave energy.  The frequency is determined by the size and shape of the cavities.

While the cavity magnetron had been proven to work, England was strapped by the war effort and did not have the resources to continue the work. [Henry Tizzard] brought the last prototype to the USA where it was described as “the most valuable cargo ever brought to our shores”. The cavity magnetron went on to be used throughout the war in RADAR systems both air and sea.

Today, many military RADAR systems use klystrons or traveling wave tube amplifiers due to requirements for accurate frequency pulses.  But the cavity magnetron still can be found in general and commercial aviation RADAR systems, as well as the microwave ovens we all know and love.

Check the video out after the break.

Continue reading “The Device That Won WW2: A History Of The Cavity Magnetron”

Maker Faire Hannover: The Right Way To Do It

On these pages we bring you plenty of reports from events, most of which are from the hacker or hardware communities. These can be great fun to attend, but they’re not the only game in town when looking at things adjacent to our community. At what you might describe as the consumer end of the market there are the Maker Faires, which bring a much more commercial approach to a tech event. While so many of us are in Germany for Chaos Communication Camp there’s a maker faire ideally placed to drop in on the way back. We took the trip to Hannover, a large and rather pleasant city just off the Berlin to Amsterdam motorway roughly central to the top half of the country. It’s got one of the German emissions zones so without the green tax sticker in the car we took a park-and-ride on one of their clean and efficient trams to alight a short walk from the congress centre.

Plenty To See, And It’s Not All For Kids

Continue reading “Maker Faire Hannover: The Right Way To Do It”

PCB Toaster Oven Solders Your Boards

Using a toaster oven to reflow PCBs isn’t anything new, but just using a toaster oven has some limitations. Making toast isn’t as complex as reflowing PCBs. [Nabil] decided to modify an oven to get better results. In fact, this was the second iteration and involved making a custom PCB to replace the one in the oven. You can see the unit in the video below.

Of course, unless you have the exact oven (a Breville BOV450XL), you won’t want to duplicate the board, but it might give you some good ideas. The new board has a 2.8-inch capacitive LCD, an ESP32, and a few sensors and actuators.

Continue reading “PCB Toaster Oven Solders Your Boards”