The GENIAC Lives Again

[Mike Gardi] credits his professional successes in the world of software development on the fact that he had access to logic-based educational games of a sort that simply don’t exist anymore. Back in the 1960s, kids who were interested in electronics or the burgeoning world of computers couldn’t just pick up a microcontroller or Raspberry Pi. They had to build their “computers” themselves from a kit.

One of those kits was the GENIus Almost-automatic Computer (GENIAC), a product which today is rare enough to essentially be unobtainable. Using images and documentation he was able to collect online, [Mike] not only managed to create a functioning replica of the GENIAC, but he even took the liberty of fixing some of the issues with the original 60-odd year old design.

Fundamentally, the GENIAC is composed of rotary switches which feed into each other to perform rudimentary logical functions. With banks of incandescent bulbs serving as the output, users could watch how placing the switches in different positions would influence the result.

This might seem a little silly to modern audiences, but thanks to a well written manual that featured a collection of compelling projects, the GENIAC managed to get a lot of mileage out of a couple light bulbs and some wire. In fact, [Mike] says that the GENIAC is often considered one of the first examples of an interactive electronic narrative, as the carefully crafted stories from the manual allowed players to go on virtual adventures long before the average kid had ever heard of a “video game”. A video about how one of these stories, “The Uranium Shipment and the Space Pirates“, can be seen after the break. Even today it would be an interesting enough toy, but back in 1955 it would have been mind-blowing.

Construction of this replica will require access to a laser cutter so you can approximate the original’s drilled Masonite backing and rotors. From there, [Mike] has produced an array of 3D printable components which are attached to the board to serve as contacts, spacers, and various other pieces of bric-a-brac. Some of the parts he couldn’t find pictures of, so he was forced to come up with his own designs. But considering the finicky nature of the original, he thinks his printed parts may actually be better than what the toy shipped with.

If you like his work with GENIAC, be sure to check out the 3D printed replica of “The Amazing Dr. Nim” that [Mike] made last year, or his breathtaking recreation of the Minivac 601.

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Cash Register Hotkey Board Is On The Money

When presented with a pile of free electronics, sometimes you grab things for their ‘someday’ potential. Other times, you know exactly what you’re after. [Bryce] got a big old cash register for free from school because they’ve moved on to using Square or something. He scored two VFDs and a solenoid as a side effect, but he was really after that sturdy keypad and its paper-label keycaps, ripe for customization.

Two hours of reverse engineering later, he knew where the button presses were going well enough to reach for a knockoff Arduino Pro Micro and a couple of shift registers. [Bryce] wanted his hotkey-board to handle keyboard presses as well as media key input, so he went with the HID-Project library over the standard-issue Arduino version. Of course, the whole point of making your own hotkey-board is customization. For [Bryce], that means Word shortcuts and quick access to Greek letters for all those engineering reports he must write. Dig that Half-Life lambda!

What? You don’t have access to free electronics? You could make a hotkey-board out of arcade buttons. Those things can really take a beating.

Putting Carbs On A Miata, Because It’s Awesome

Carburettors versus electronic fuel injection (EFI); automotive fans above a certain age will be well versed in the differences. While early EFI systems had their failings, the technology brought with it a new standard of reliability and control. By the early 1990s, the vast majority of vehicles were sold with EFI, and carburettors became a thing of the past.

The Mazda Miata was no exception. Shipping in 1989, it featured not only multiport fuel injection, but also a distributorless ignition system. Consisting of two coilpacks in a wasted spark configuration, with computer-controlled timing, the system was quite advanced for its time, especially for a budget sports car.

Despite the Miata’s technological credentials, those in the modified car scene tend to go their own way. A man by the name of Evan happened to be one such individual and decided to do just this — scrapping the EFI system and going with a retro carburetor setup. It was around this point that this I got involved, and mechanical tinkering ensued.

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This WiFi Spoofing Syringe Is For External Use Only

A browse through his collected works will tell you that [El Kentaro] loves to build electronics into interesting enclosures, so when he realized there’s enough room inside a 150 ml plastic syringe to mount an ESP8266, a battery, and a copious amount of RGB LEDs, the “Packet Injector” was the inescapable result.

Granted, the current incarnation of this device doesn’t literally inject packets. But [El Kentaro] wasn’t actually looking to do anything malicious, either. The Injector is intended to be a fun gag for him to bring along to the various hacker cons he finds himself at, like his DEAUTH “bling” necklace we saw at DEF CON 26, so having any practical function is really more icing on the cake than a strict requirement.

In the end, the code he came up with for the Adafruit Feather HUZZAH that uses the FakeBeaconESP8266 library to push out fictitious networks on demand. This is a trick we’ve seen used in the past, and makes for a relatively harmless prank as long as you’re not pumping out any particularly unpleasant SSIDs. In this case, [El Kentaro] punctuates his technicolor resplendency with beacons pronouncing “The WiFi Doctor is Here.”

But the real hack here is how [El Kentaro] controls the device. Everything is contained within the syringe chamber, and he uses a MPL3115A2 I2C barometric pressure sensor to detect when it’s being compressed. If the sensor reads a pressure high enough over the established baseline, the NeoPixel Ring fires up and the fake beacon frames start going out. Ease up on the plunger, and the code detects the drop in pressure and turns everything back off.

If this build has piqued your interest, [El Kentaro] gave a fascinating talk about his hardware design philosophy during the WOPR Summit that included how he designed and built some of his “greatest hits”; including a Raspberry Pi Zero enclosure that was, regrettably, not limited to external use.

Kitty Litter And Broken Light Bulbs Power This Homebrew Gas Chromatograph

We’re always on the lookout for unexpected budget builds here at Hackaday, and stumbling across a low-cost, DIY version of an instrument that sells for tens of thousands of dollars is always a treat. And so when we saw a tip for a homebrew gas chromatograph in the tips line this morning, we jumped on it. (Video embedded below.)

For those who haven’t had the pleasure, gas chromatography is a chemical analytical method that’s capable of breaking a volatile sample up into its component parts. Like all chromatographic methods, it uses an immobile matrix to differentially retard the flow of a mobile phase containing the sample under study, such that measurement of the transit time through the system can be made and information about the physical properties of the sample inferred.

The gas chromatograph that [Chromatogiraffery] built uses a long stainless steel tube filled with finely ground bentonite clay, commonly known as kitty litter, as the immobile phase. A volatile sample is injected along with an inert carrier gas – helium from a party balloon tank, in this case – and transported along the kitty litter column by gas pressure. The sample interacts with the column as it moves along, with larger species held back while smaller ones speed along. Detection is performed with thermal conductivity cells that use old incandescent pilot lamps that have been cracked open to expose their filaments to the stream of gas; using a Wheatstone bridge and a differential amp, thermal differences between the pure carrier gas and the eluate from the column are read and plotted by an Arduino.

The homebrew GC works surprisingly well, and we can’t wait for [Chromatogiraffery] to put out more details of his build.

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A Post-Mortem For An Electric Car Charger

[Mastro Gippo] recently purchased a wall mounted charger for his electric car that looked great and had all the bells and whistles he wanted. There was only one problem: the thing burned up on him. Looking to find out how this seemingly high-end piece of hardware gave up the ghost so easily, he took it apart and tried to figure out where things went wrong. While he’s not looking to sling any mud and actually name the company who produced the charger, he certainly has some choice words for whoever green-lit this particular design.

With the charger open, there’s little doubt that something became very toasty inside. A large swath of the PCB has a black char mark on it, and in some places it looks like the board burned right through. After a close examination, [Mastro] is of the opinion that the board heated up to the point that the solder actually liquified on some connections. This conductive flow then shorted out components below it, and things went from bad to worse.

But where did all the heat come from? [Mastro] was stunned to see that a number of the components inside the charger were only rated for 30 amps, despite the label for the product clearly stating it’s good for up to 32A. With components pushed past their limits, something had to give. He wonders how such a device could have made it through the certification process; an excellent question we’d love to know the answer to.

The worst part is, it looks like the designers might have even known there was an overheating issue. [Mastro] notes that there are heatsinks bolted not to a component as you might assume, but directly to the PCB itself. We’ve seen what happens when designers take a cavalier attitude towards overheating components, and the fact that something like an electric vehicle charger was designed so poorly is quite concerning.

Blue Pill Makes Cheap But Powerful Morse Tutor

[W8BH] attended a talk by another ham, [W8TEE] that showed a microcontroller sending and receiving Morse code. He decided to build his own, and documented his results in an 8 part tutorial. He’s using the Blue Pill board and the resulting device sends code with paddles, sends canned text, provides an LCD with a rotary knob menu interface, and even has an SD card for data storage.

All the code is on GitHub. If you are interested in Morse code or in learning how to write a pretty substantial application using the Blue Pill and the Arduino IDE (or any other similar processor), this is a great exposition that is also a practical tool.

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