Macintosh Classic II With E-Ink Display

August 24, 2022 by Bryan Cockfield 30 Comments

As various antique computers age, it becomes increasingly hard to operate them as hardware begins to physically fail. Keeping these systems up and running often requires scavenging parts from other machines which are only becoming harder to find as time goes on. But if you throw out the requirement of using only era-appropriate components, there are some interesting ways to revive older devices with a few touches of modern tech, like this Mac Classic with a unique display.

The Macintosh Classic II was the successor to the first Macintosh computer Apple sold that had a price tag under $1000. As such, there were some lower specs for this machine such as the monochrome 512×342 display. This one has been retrofitted with an e-ink display which actually gives it some of the same grayscale aesthetic as the original. The e-ink display is driven by a Raspberry Pi which displays a replica System 7 environment and a set of photos.

While the only part of the computer that’s original is the shell at this point, the project’s creator [Dave] also built in support for the Apple Desktop Bus through an Arduino so the original Apple mouse and keyboard can be used. While it’s largely an illusion of a working Mac Classic, we still appreciate the aesthetic.

If you’re more of a classic Apple purist, though, take a look at this SE/30 which uses almost entirely original parts with the exception of a Raspberry Pi to allow it to communicate with the modern Internet.

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Frequency Counter Restoration Impeded By Kittens

August 24, 2022 by Al Williams 12 Comments

We think of digital displays as something you see on relatively modern gear. But some old gear had things like nixies or numitrons to get cool-looking retro digital displays. The HP 521A frequency counter, though, uses four columns of ten discrete neon bulbs to make a decidedly low-tech but effective digital display. [Usagi Electric] has been restoring one of these for some time, but there was a gap between the second and third videos as his workshop became a kitten nursery. You can see the last video below.

In previous videos, he had most of the device working, but there were still some odd behavior. This video shows the final steps to success. One thing that was interesting is that since each of the four columns are identical, it was possible to compare readings from one decade to another.

However, in the end, it turned out that the neon bulbs were highly corroded, and replacing all the neon bulbs made things work better. However, the self-check that should read the 60 Hz line frequency was reading 72 Hz, so it needed a realignment. But that was relatively easy with a pot accessible from the back panel. If you want to see more details about the repair, be sure to check out the earlier videos.

We love this old gear and how clever designers did so much with what we consider so little. We hate to encourage your potential addiction, but we’ve given advice on how to acquire old gear before. If you want to see what was possible before WS2812 panels, you could build this neon bulb contraption.

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There’s Gold In That There Graphene

August 23, 2022 by Al Williams 14 Comments

There’s gold all around us, embedded in our electronics. There are people who collect e-waste and use various methods to extract gold from them. However, it is hard to qualify it as a “get rich quick” scheme because the amount of gold recovered is usually minute. Still, if you can do volume, you can make some money and recycling is always a good idea. At the University of Manchester, they have a better way to extract gold from e-waste using graphene. You can see a brief video about the process below, or read the full paper.

The process is relatively simple. You dissolve the e-waste in a solvent, add some graphene oxide, and the gold appears bound to the graphene. You pull out the graphene and burn it off to result in the gold you want. A gram of graphene can grab 2 grams of gold and graphene is relatively cheap per gram compared to gold.

Graphene oxide nanosheets are processed using ascorbic acid into a colloid suspension. The chemical process converts gold bound with chlorine into elemental gold. After diving into why the process works, they were able to increase the selectivity of the process by manipulating the pH so that the majority of the residue is actually gold.

The team believes they can build a continuous process that takes liquefied e-waste and extracts gold as it flows through the system. If you’d rather go with the traditional method, here’s a start for you. Then again, there are other metals to recover besides gold.

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Integrated Circuit Manufacturing At Bell Labs In 1983

August 23, 2022 by Dave Rowntree 13 Comments

With the never ending march of technological progress, arguably the most complex technologies become so close to magic as to be impenetrable to those outside the industry in which they operate. We’ve seen walkthrough video snapshots of just a small part of the operation of modern semiconductor fabs, but let’s face it, everything you see is pretty guarded, hidden away inside large sealed boxes for environmental control reasons, among others, and it’s hard to really see what’s going on inside.

Let’s step back in time a few decades to 1983, with an interesting tour of the IC manufacturing facility at Bell Labs at Murray Hill (video, embedded below) and you can get a bit more of an idea of how the process works, albeit at a time when chips hosted mere tens of thousands of active devices, compared with the countless billions of today. This fab operates on three inch wafers, producing about 100 die each, with every one handled and processed by hand whereas modern wafers are much bigger, die often much smaller with the total die per wafer in the thousands and are never handled by a filthy human.

Particle counts of 100 per cubic foot might seem laughable by modern standards, but device geometries back then were comparatively large and the defect rate due to it was not so serious. We did chuckle somewhat seeing the operator staff all climb into their protective over suits, but open-faced with beards-a-plenty poking out into the breeze. Quite simply, full-on bunny suits were simply not necessary. Anyway, whilst the over suits were mostly for the environment, we did spot the occasional shot of an operator wearing some proper protective face shielding when performing some of the higher risk tasks, such as wafer cleaning, after all as the narrator says “these acids are strong enough to eat through the skin” and that would certainly ruin your afternoon.

No story about integrated circuit processing would be complete without mentioning the progress of [Sam Zeloof] and his DIY approach to making chips, and whilst he’s only managing device counts in the hundreds, this can only improve given time.

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Flapping PCB Fan Blows A Little Bit

August 23, 2022 by Danie Conradie 23 Comments

Moving air with spinning blades is the most popular way, but it is not the only way. Using the PCB actuator technology he has been working on for the past few years, [Carl Bugeja] built a small electromagnetic flapping fan using a custom flexible PCB.

Inspired by expensive piezoelectric fans ($400 for a 30mW fan), [Carl] wanted to see if a cheaper alternative could be made. Using a similar design to his other PCB actuators, he had a custom flexible PCB made with an integrated coil, which can flex on two thin supports. These supports also contain the power traces for the coil. By sticking the base of the PCB between two neodymium magnets, it can flap back and forth when driven by an alternating current. It produces a bit of airflow, but nearly enough to be useful. The power traces in the thin supports also break after an extended period of 180° flapping.

Although this probably won’t be a viable replacement for a rotary fan, it would be interesting to see how far one can push this approach by optimizing the design and magnet arrangement.

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High-Speed RC Car Needs A Flight Controller

August 23, 2022 by Danie Conradie 2 Comments

The fastest ground vehicles on earth are not driven by their wheels but by an aircraft jet engine. At world record speeds, they run on an aerodynamic razor’s edge between downforce, which limits speed, and liftoff, which can result in death and destruction. [rctestflight] wanted to see what it takes to run an RC car at very high speeds, so he built a ducted-fan powered car with aerodynamic control surfaces and an aircraft flight controller.

This high-speed car is built on the chassis of a 1/14th scale RC buggy, powered by 4 EDF (electric ducted fans) mounted on a very long aerodynamic foam board shell. It also has an aircraft-style tail with elevons and rudders for stabilization and control at high speed using an ArduPilot flight controller. The flight controller is set up to stabilize in the roll and yaw axis, with only fixed trim in the pitch axis.

[rctestflight] got the car up to 71 MPH (114 km/h), which is fast for most RC cars but well short of the 202 MPH RC car speed record. It was still quite hard to keep in a straight line, and the bumpy roads certainly didn’t help. He hopes to revisit the challenge in the future with larger motors and high voltage batteries.

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2022 Hackaday Prize: Plant Monitoring System Grows To Include LoRa

August 23, 2022 by Bryan Cockfield 7 Comments

Change on industrial scales is slow, but if you’re operating your own small farm or simply working in a home garden there are some excellent ways to use water more effectively. The latest tool from [YJ] makes it possible to use much less water while still keeping plant yields high.

This is an improvement on a previous project which automates watering and lighting of a small area or single pot. This latest creation, called FLORA, includes a LoRa module for communication up to 3 kilometers, and the ESP32 on board also handles monitoring of soil moisture, humidity and other sensors. It also includes a pump driver for managing irrigation systems so that smart decisions can be made about when to water. Using this device, the water usage when testing was reduced by around 30% compared to a typical timed irrigation system.

Using a smart system like this is effective for basically any supply of water, but for those who get water from something like an off-grid rainwater system or an expensive water utility, the gains are immediate. If you aren’t already growing your own food to take advantage of tools like this, take a look at this primer to get you started.