Working LEGO Space Computers Are A Chip Off The Old Block

August 4, 2021 by No comments

We all have our favorite classic LEGO bricks, and wouldn’t be surprised if one or more of the various space computers showed up on pretty much everyone’s list. [dyoramic] loves them so much that they built two different working versions that do different things.

The first one is about six times the size of the original brick. Inside the 3D printed case is an ESP32 and a 1.5″ OLED display. [dyoramic] wired up the top six buttons as inputs and the rest are just for looks. The screen defaults to the classic white cross on green that just sits there looking legit. But start pushing buttons and you’ll find other modes — the cross becomes a radar screen in one, the computer spits out space facts in another, there’s a falling bricks game, and finally, a time and date screen.

The second LEGO space computer build is even bigger — both were designed around the size of their screens. It has a Raspi 4 and shows a dashboard with the weather, time, date, latest xkcd, and a few cryptocurrency prices. [dyoramic] has an even bigger version in the works that will use a 720 x 720 screen and a handful of brown key switches as inputs. We can’t wait to see that one! For now, check out the build and demo of the first two after the break.

What can’t you do with LEGO? It feels like we’ve seen it all, from cameras to microscopes to continuously variable transmissions. Wouldn’t you love to drive one of those around the block?

Continue reading “Working LEGO Space Computers Are A Chip Off The Old Block” →

How To Modify Your Car Stereo For Bluetooth Or Aux-In

July 28, 2021 by 42 Comments

If you’re an automotive enthusiast of taste, you can’t stand the idea of fitting a janky aftermarket stereo into your nice, clean ride. Flashy, modern head units can spoil the look of a car’s interior, particularly if the car is a retro, classic, or vintage ride.

Thus, we’re going to look at how to modify your existing stock car stereo to accept an auxiliary cable input or even a Bluetooth module. This way, you can pump in the latest tunes from your smartphone without a fuss, while still maintaining an all-original look on the dash.

Fundamentals

A simple Bluetooth module designed for wiring into car audio systems. There are two wires for 12 V power from the vehicle, and the audio signal is sent out over the RCA plugs. The RCA plugs can be cut off and the module hard wired inside your stereo if you have room. Cutting off the plastic case can help too.

Depending on your choice of audio player, you may prefer a 3.5 mm aux jack, or you might want to go with Bluetooth audio if your smartphone no longer has a headphone port. Whichever way you go, the process of modifying the stereo is largely the same. To achieve your goal, you need to find a way of injecting the audio signal into the head unit’s amplifier stage, while making sure no other audio sources are getting sent there as well.

Whether that audio source is a 3.5 mm jack or a Bluetooth module doesn’t matter. The only difference is, in the latter case, you’ll want to buy a Bluetooth module and hardwire it in to the auxiliary input you create, while also splicing the module into the stereo’s power supply. In the case of a simple headphone jack input, you simply need to wire up an aux cord or 3.5 mm jack somewhere you can get to it, and call it done.

This guide won’t cover every stereo under the sun, of course. Edge cases exist and depending on the minute specifics of how your original car radio works, these exact methods may or may not work for you. However, this guide is intended to get you thinking conceptually about how such mods are done, so that you can investigate the hardware in front of you and make your own decisions about how to integrate an external audio input that suits your usage case. Continue reading “How To Modify Your Car Stereo For Bluetooth Or Aux-In” →

Teardown: VTech Smart Start

July 12, 2021 by 12 Comments

Regular readers may be aware that I have a certain affinity for vintage VTech educational toys, especially ones that attempted to visually or even functionally tie in with contemporary computer design. In the late 1980s, when it became obvious the personal computer was here to stay, these devices were seen as an affordable way to give kids and even young teens hands-on time with something that at least somewhat resembled the far more expensive machines their parents were using.

Much Smarter: VTech PreComputer 1000

A perfect example is the PreComputer 1000, released in 1988. Featuring a full QWERTY keyboard and the ability to run BASIC programs, it truly blurred the line between toy and computer. In fact from a technical standpoint it wasn’t far removed from early desktop computers, as it was powered by the same Zilog Z80 CPU found in the TRS-80 Model I.

By comparison, the Smart Start has more in common with a desktop electronic calculator. Even though it was released just two years prior to the PreComputer 1000, you can tell at a glance that it’s a far more simplistic device. That’s due at least in part to the fact that it was aimed at a younger audience, but surely the rapid advancement of computer technology at the time also played a part. Somewhat ironically, VTech did still at least attempt to make the Smart Start look like a desktop computer, complete with the faux disk drive on the front panel.

Of course, looks can be deceiving. While the Smart Start looks decidedly juvenile on the outside, that doesn’t mean there aren’t a few surprising technical discoveries lurking under its beige plastic exterior. There’s only one way to find out.

Continue reading “Teardown: VTech Smart Start” →

Custom Car Horn Makes Many Sounds

July 9, 2021 by 29 Comments

A regular car horn is fine, but lacks finesse for more subtle communication. For example, some car horns aren’t particularly adept at short indicatory honks, and can only blare loudly regardless of the situation. For a fancier solution, [Tom Hammond] whipped up a custom car horn capable of playing a wide variety of sounds.

The system uses the Adafruit Audio FX board. This is a unique part, which is designed to enable people to build sound-based projects without the need for a microcontroller or any other similar hardware. Instead, the device can be connected to a computer over USB in mass storage mode, and its 16MB in-built memory can be loaded with sound files. It then plays these when buttons are pressed, hooked up to its 11 trigger inputs.

The Audio FX board has its output hooked up to a 120W amplifier, which then feeds into a pair of 15W PA-style horns. These are incredibly loud devices, though lack bass, so they’re really only good for throwing low-quality sound out in a noisy environment. For a car horn, that’s perfect.

The result is that [Tom] can press a number of buttons on his dash to play different sounds, from courtesy honks to animal noises and obnoxious sound effects. The great thing is that the sounds in question can be easily customized to the user’s tastes. [Tom] also deserves a tip of the hat for explaining in great detail how to actually install the project in the average car.

We don’t often see car horns around these parts, though they do make for an awfully loud alarm clock. If you’ve got your own nifty car accessories that you’re cooking up, be sure to drop us a line!

Tech Hidden In Plain Sight: Cruise Control

July 8, 2021 by 29 Comments

The advent of the microcontroller changed just about everything. Modern gadgets often have a screen-based interface that may hide dozens or hundreds of functions that would have been impractical and confusing to do with separate buttons and controls. It also colors our thinking of what is possible. Imagine if cars didn’t have cruise control and someone asked you if it were possible. Of course. Monitor the speed and control the gas using a PID algorithm. Piece of cake, right? Except cruise control has been around since at least 1948. So how did pre-microcontroller cruise control work? Sure, in your modern car it might work just like you think. But how have we had seventy-plus years of driving automation?

A Little History

A flyball governor from a US Navy training film.

Controlling the speed of an engine is actually not a very new idea. In the early 1900s, flyball governors originally designed for steam engines could maintain a set speed. The idea was that faster rotation caused the balls would spread out, closing the fuel or air valve while slower speeds would let the balls get closer together and send more fuel or air into the engine.

The inventor of the modern cruise control was Ralph Teetor, a prolific inventor who lost his sight as a child. Legend has it that he was a passenger in a car with his lawyer driving and grew annoyed that the car would slow down when the driver was talking and speed up when he was listening. That was invented in 1948 and improved upon over the next few years.

Continue reading “Tech Hidden In Plain Sight: Cruise Control” →

This Week In Security: Ransomware, WeLock, And Amazon Arbitration

June 4, 2021 by 9 Comments

Another week of ransomware, and this time it’s the beef market that’s been shut down, due to a crippling infrastructure attack out of Russia — but hold up, it’s not that simple. Let’s cover the facts. Some time on Sunday, May 30, JBS USA discovered a ransomware attack against their systems. It seems that their response team did exceptionally well, pulling the plug on affected machines, and starting recovery right away. By Wednesday, it was reported that most of their operations were back in action.
Continue reading “This Week In Security: Ransomware, WeLock, And Amazon Arbitration” →

Make Android’s New Power Menu Work On Your Terms

May 14, 2021 by 7 Comments

Introduced in Android 11, the power menu is a way to quickly interact with smart home gadgets without having to open their corresponding applications. Just hold the power button for a beat, and you’ll be presented with an array of interactive tiles for all the gadgets you own. Well that’s the idea, anyway.

[Mat] of “NotEnoughTech” wasn’t exactly thrilled with how this system worked out of the box, so he decided to figure out how he could create his own power menu tiles. His method naturally requires quite a bit more manual work than Google’s automatic solution, but it also offers some compelling advantages. For one thing, you can make tiles for your own DIY devices that wouldn’t be supported otherwise. It also allows you to sidestep the cloud infrastructure normally required by commercial home automation products. After all, does some server halfway across the planet really need to be consulted every time you want to turn on the kitchen light?

Adding tiles in Tasker.

The first piece of the puzzle is Tasker, a popular automation framework for Android. It allows you to create custom tiles that will show up on Android’s power menu, complete with their own icons and brief descriptions. If you just wanted to perform tasks on the local device itself, this would be the end of the story. But assuming that you want to control devices on your network, Tasker can be configured to fire off a command to a Node-RED instance when you interact with the tiles.

In his post, [Mat] gives a few examples of how this combination can be used to control smart devices and retrieve sensor data, but the exact implementation will depend on what you’re trying to do. If you need a bit of help getting started, our own [Mike Szczys] put together a Node-RED primer last year that can help you put this flow-based visual programming tool to work for you.

Continue reading “Make Android’s New Power Menu Work On Your Terms” →