Day: April 16, 2020

Econet – Britain’s Early Educational Network

April 16, 2020 by 22 Comments

If you compare the early PC market for the US and the UK, you’ll notice one big difference. While many US schools had Apple computers, there were significant numbers of other computers in schools, as well. In the UK, pretty much every school that had a computer had an Acorn BBC Micro. [RetroBytes] takes us down memory lane, explaining how and why the schools went with Econet — an early network virtually unknown outside of the UK. You can see the video, which includes an interview with one of the Acorn engineers involved in Econet.

Nowadays, you don’t have to convince people of the value of a network, but back then it wasn’t a no brainer. The driver for most schools to adopt networking was to share a very expensive hard disk drive among computers. The network used RS-422, a common enough choice in Apple computers, spacecraft, and industrial control applications.

Continue reading “Econet – Britain’s Early Educational Network” →

The Three Shell Mystery Finally Solved!

April 16, 2020 by 9 Comments

While we certainly acknowledge the valuable contributions of the open hardware community that help to mitigate the coronavirus crisis, we are also looking forward to the days when people start going back to building other things than 3D-printed face shields, pandemic trackers, and automatic soap dispensers. However, this handwash timer by [Agis Wichert] is a very creative version that also tries to solve the long outstanding mystery of how to use the three seashells. Unfortunately, in contrast to those in the original movie, these three seashells do not replace toilet paper which many people are seemingly so desperate in need of at the moment.

The build is quite simple and requires only a few off-the-shelf components including a Neopixel strip, IR proximity sensor, and an Arduino Nano. The plastic seashells were taken from the classic German “Schleckmuschel” candy, thereby giving the project an extra retro twist. As shown in the video embedded below, the timer works by consecutively dimming the LEDs located under each seashell until the recommended duration of 20 seconds has elapsed which is indicated by shortly flashing all LEDs.

Handwash timer projects do not always have to be visual as this one playing your favorite Spotify tunes proves. What we really would like to see though is someone building a toilet paper dispenser that is triggered by swearwords.

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Automatic Timelapses, Made Educational And Easy

April 16, 2020 by 2 Comments
Timelapse fragment from an infrared sky camera watching cloud patterns.

There are plenty of ways to create timelapse videos, but [Andy] has an efficient method for ensuring up-to-date ones exist for his infrared sky camera, and he has it running thanks to some well-documented shell scripts on a spare Raspberry Pi. The resulting timelapse video is always available from the web, and always up-to-date for the current day.

The idea is to automatically fetch images from a remote source (in his case, an infrared sky camera) and turn them into a cumulative video that is regularly updated for the day in question. The resulting video file is either served from the same machine, or sent elsewhere. All that’s needed besides a source for the stills are two shell scripts and some common Linux utilities.

Since [Andy] is mainly interested in tracking clouds his system only runs during daylight hours, but it can be easily changed. In fact, [Andy]’s two shell scripts are great project resources, not only because they are easily modified and well documented, but because he doesn’t make assumptions about how well one might know the command line. He also provides tips from experience; for example he has found that a 120 second interval makes for the best timelapses.

[Andy] runs his scripts on an Raspberry Pi 4, but any Linux system will do. For those who might prefer a more embedded approach, the ESP32-CAM can make a great time lapse camera with remarkably little effort.

Puttering Around In A Converted Golf Cart

April 16, 2020 by 16 Comments

Technically speaking, golf carts are already sports cars, they’re just not very sporty in themselves. When [rtkerth] went to trade in his old golf cart for a new one, he found that it would be more valuable to hang on to the old one and have a bit of fun with it. The result is retro-styled kart that would not look out of place at a micro car show.

Before getting to the really fun bits, he had to do a bit of prep work, such as relocating the six large batteries so that super cool stock seat can sit lower. Now the batteries are distributed throughout the vehicle, including one that’s been cleverly disguised as center console. Since the cart won’t be hitting the links anymore, there’s no need for a place to put clubs. Two of the batteries are now in the back, supported by a platform made from old bed frames.

We love the fiberglass fab work [rtkerth] did to the front and rear — it looks great, especially considering he’d never done it before. The rear is done more traditionally with a foam mold, but the front is fiberglassed directly over expanding foam insulation framed with cardboard. The local body shops refused to paint this baby roadster, so [rtkerth] did it himself before adding the killer touches — 1930s Brooklands-style windscreens and 1950s bullet mirrors that look great together.

Believe it or not, this isn’t the first amazing golf cart mod we’ve seen. Go see this baby DeLorean before you’re outta time.

As A Matter Of Fact, It’s All Dark

April 16, 2020 by 41 Comments

While the dark side of the moon wasn’t seen by humans until the middle of the 20th century, that side of the moon isn’t always dark, just hidden from view of Earth by a quirk of gravity. The more appropriate name for the other half of the moon is the “far side”, but while it gets just as much sunshine as the near side does it is dark to one thing in particular: man-made radio waves. That, along with the lack of an atmosphere and ionosphere on the moon, makes it a perfect place for a new telescope.

This telescope isn’t like something you’d set up in your back yard, either. It’s more similar to the Aricebo Observatory in Puerto Rico which uses natural topography to help form the telescope. The proposed telescope on the far side of the moon would use a robot to deploy a net along a fairly large crater to act as a parabolic dish, while another robot would suspend the receiver above the crater. The large size is necessary for viewing deep into space, but is also because of the low-frequency radio signals they hope to capture.

Building a dish like this on the moon is sure to be no easy task, especially since remote control on the far side of the moon is difficult for precisely the reasons that make this a good location for a telescope. But with an appropriate amount of funding and some sufficiently autonomous robots it should be possible. Plus, you never know what you’ll find when looking deep into space.

How To Get Into Cars: Forced Induction

April 16, 2020 by 43 Comments

For those addicted to automotive thrills, there’s always an underlying lust for more power. For those chasing a bigger number, forced induction is one of the most effective ways to achieve it. In addition to more grunt, you get a whole bunch of fun new noises, too.  For those with a naturally aspirated car, here’s how you go about converting to forced induction.

Superchargers and Turbos

When we talk about forced induction, we’re talking about forcing more air into the engine under pressure. With more air available, it’s possible to fully combust more fuel, creating more power. The two most common ways of doing this are supercharging and turbocharging. We’ll be using the common automotive vernacular here, so those eager to bicker about terminology from the early 20th century aircraft industry best do it in the comments. Continue reading “How To Get Into Cars: Forced Induction” →

Software Shortcut Keyboard Registers Many Macros

April 16, 2020 by 18 Comments

[FabroLabs Technologies] is an industrial designer who uses several creative-type software programs in a given day. Unfortunately, they all have slightly different shortcut schemes, and trying to remember all the different modifiers is a waste of time better spent elsewhere.

This lovely little macro keyboard is every bit as useful as it is cool looking. Spinning the rotary encoder cycles through a menu of programs on the 16×2 LCD, and the key map just updates automatically for the chosen program. At the heart of this build is an Arduino Pro Micro and 20 of the loudest key switches ever made — Cherry MX blues. We like that it manages to look like toy cash register and a serious peripheral all at once — it probably has something to do with those way-cool circular keycaps that were made on a resin printer.

We’re glad that [FabroLabs] laid down such a comprehensive and open build guide during the process of making this macro keyboard. The average hacker can learn a lot from industrial designers who show their work. Remember the time [Eric Strebel] showed us all how to improve our foam board design game?