Year: 2022

The Sinclair ZX Spectrum Turns 40

April 26, 2022 by 68 Comments

It’s an auspicious moment for retrocomputing fans, as it’s now four decades since the launch of the Sinclair ZX Spectrum. This budget British microcomputer was never the best of the bunch, but its runaway success and consequent huge software library made it the home computer to own in the UK. Here in 2022 it may live on only in 1980s nostalgia, but its legacy extends far beyond that as it provided an entire generation of tech-inclined youngsters with an affordable tool that would get them started on a lifetime of computing.

What Was 1982 Really Like?

Cover of Sincalir User, Sir Clive Sinclair as a magician
Sinclair User issue 3 captures the excitement surrounding the Spectrum launch.

There’s a popular meme among retro enthusiasts that the 1980s was a riot of colour, pixel artwork, synth music, and kitschy design. The reality was of growing up amid the shabby remnants of the 1970s with occasional glimpses of an exciting ’80s future. This was especially true for a tech-inclined early teen, as at the start of 1982 the home computer market had not yet reached its full mass-market potential. There were plenty of machines on offer but the exciting ones were the sole preserve of adults or kids with rich parents. Budget machines such as Sinclair’s ZX81 could give a taste of what was possible, but their technical limitations would soon become obvious to the experimenter.

1982 was going to change all that, with great excitement surrounding three machines. Here in the UK, the Acorn BBC Micro had been launched in December ’81, the Commodore 64 at the start of ’82, and here was Sinclair coming along with their answer in the form of first the rumour of a ZX82, and then the reality in the form of the Spectrum.

This new breed of machines all had a respectable quantity of memory, high-res (for the time!) colour graphics, and most importantly, sound. The BBC Micro was destined to be the school computer of choice and the 64 was the one everybody wanted, but the Spectrum was the machine you could reasonably expect to get if you managed to persuade your parents how educational it was going to be, because it was the cheapest at £125 (£470 in today’s money, or about $615). Continue reading “The Sinclair ZX Spectrum Turns 40” →

Hand-Built Metal Mouse Is Beautifully Engraved

April 26, 2022 by 19 Comments

Computer mice, like computers themselves, used to be built almost solely in hideous beige designs. These days, things are a bit more stylish, but they’re still largely following a simple plastic formula. [Uri Tuchman] decided to build a fancy metal engraved computer mouse for a little more style on the desktop.

The build starts by gutting a simple three-button scroll mouse, as there’s really no sense in reinventing the wheel where the electronics is concerned. The PCB inside is pulled out and assembled on a brass baseplate, along with standoffs and supports for the mouse wheel as needed. It’s paired with a hefty brass enclosure with a nice gentle slope to sit well in the hand. Or, as well as it can, given the square  metal edges of the finished product.

The build is full of fun details, like [Uri] trying to form a hex shaft by hand, and the work that goes into the engraving is similarly impressive. In any case, it’s a build that would pair wonderfully with a proper steampunk keyboard. Alternatively, if you hate the idea of having to do all that engraving by hand, think about building your own CNC machine. Video after the break.

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Physical Control Panel Elevates Flight Sim Experience

April 26, 2022 by 11 Comments

Like so many of us, [pgsanchez] has been bitten by the flight simulator bug. It’s a malady that can only be treated, but never cured — and like so many hobbies, it has a nasty tendency to spawn more hobbies. A software developer by trade, [pgsanchez] is also adept with Arduino and electronics, and his blog post about the PGS-2 Flight Simulator Control Panel demonstrates his fine abilities well, as does the video below the break.

A player of Digital Combat Simulator, he grew tired of having to remember awkward key combinations to control the simulator. Flying a jet, even in a simulator, can require quick thinking bound with quick reflexes, so having a button to press, a switch to flip, or a knob to turn can be vastly superior to even the simplest keyboard based command.

An Arduino interfaces the buttons to the computer, and a white acrylic case is employed to keep all the parts flying in formation. Yes, a white case — with great care taken to allow the case to be backlit. The effect is excellent, and it looks like the panel would be right at home in the Sukhoi Su-25T that it’s designed to control in the game.

We appreciated the attention to detail in the panel, as even the gear status lights and flap indicators match those in the simulator, a nice touch! What more could [pgsanchez] build? We’d like to see! If you’re into flight sims and the like, you might be interested in this fully 3D printed flight sim controller.

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Lofipi Keeps The Chill Beats Coming

April 25, 2022 by 21 Comments

These days, many people love having some lo-fi beats on when they chill and study. This has led to a cottage industry dedicated to producing said beats, and the format continues to grow in popularity. [Nicholas Sherlock] decided to build a custom audio device solely for the delivery of these comfortable tunes.

As seen on Reddit, the build relies on a Raspberry Pi 3B, paired with an X400 audio amplifier board and hooked up to a nicely-sized mid-range speaker. The hardware is assembled inside a case printed out of wood-effect PLA filament, giving it a nice old-school home audio aesthetic. As a bonus, the layer lines line up in such a way as to boost the woodgrain effect. Plug it in, and you will be immediately rewarded with lo-fi beats from boot.

Originally, the system ran a port of the code from lofigenerator.com, which algorithmically creates lo-fi beats from scratch. However, [Nicholas] could not in good conscience share the ported code, and has retooled the system to stream YouTube playlists using command line media player mpv instead. It’s set to stream typical lo-fi playlists, though could be repurposed to target anything on the platform.

It’s a nice build that really suits the lo-fi beats ideal. When you’re trying to study or focus, you don’t want to be mucking around with a YouTube tab open serving as a distraction. Instead, you can simply flick on the Lofipi, and vibe out.

The Raspberry Pi’s cheap price and great internet and media capabilities make it very popular for builds like these. They go some way to recreating the idea of receiving a broadcast, rather than forcing us into choice as per today’s modern on-demand media paradigm. If you’ve got thoughts on this, drop them in the comments, and if you’ve got your own great projects, do drop us a line.

Learning Electronics By Just Doing It

April 25, 2022 by 33 Comments

Learning anything new, especially so broad and far reaching as electronics, can be hard. [IMSAI Guy] knows this because he gets asked regularly “how do I learn electronics?” Many of you reading this will have a few ideas to pass along (and we encourage you to share your take on it in the comments below) but there is an even greater number of people who are asking the same question, and [IMSAI Guy]’s take on it is one that this particular Hackaday writer can relate to.

The ARRL Handbook can be found at hamfests, radio clubs, libraries, or at arrl.org

According to [IMSAI Guy], an excellent place to start is the ARRL Handbook. The ARRL Handbook is an electronics and RF engineering guide published by the Amateur Radio Relay League in the US. It’s a wonderful reference, and past editions can be had very inexpensively and are every bit as handy. Many hams will have a copy they could be talked out of, and you can likely find one at your local library. Where to start in the Handbook, then?

[IMSAI Guy] recommend starting with whatever catches your fancy. As an example, he starts with Op Amps, and rather than diving straight into the math of how they work or even worrying to much about what they are- he just builds a circuit and then plays with it to intrinsically understand how it works, a “learn by doing” approach that he has found extremely helpful just as many of us have. We also appreciated is very straightforward approach to the math: Don’t bother with it unless you need to for some reason, and definitely don’t start by learning it first.

In fact, that same reasoning is applied to any subject: Learn it as you need it, and don’t start by learning but rather by doing. The learning will come on its own! Be sure to check out the entire video and let us know what you think, and how you approached learning electronics. Thanks to [cliff] for the great Tip!

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The Apollo Digital Ranging System: More Than Meets The Eye

April 25, 2022 by 15 Comments

If you haven’t seen [Ken Shirriff]’s teardowns and reverse engineering expeditions, then you’re in for a treat. His explanation and demonstration of the Apollo digital ranging system is a fascinating read, even if vintage computing and engineering aren’t part of your normal fare.

The average Hackaday reader should be familiar with the concept of determining the distance of a faraway object by measuring how long it takes a sound or radio wave to be reflected, such as in sonar and radar. Going another step and measuring Doppler Shift – the difference in the returned signal’s frequency – will tell us the velocity of the object relative to our position. It’s so simple that an Arduino can do it. But in the days of Apollo, there was no Arduino. In fact, there were no Integrated Circuits. And Apollo missions went all the way to the moon- far too distant for relatively simple Radar measurements. Continue reading “The Apollo Digital Ranging System: More Than Meets The Eye” →

3D Printed Turbo Pump Hopes To Propel Rockets To The Sky

April 25, 2022 by 22 Comments

There are plenty of rocket experimenters toying with various liquid-fueled contraptions at the moment, and [Sciencish] is one of them. He grew tired of using air-pressurized fuel delivery systems in his experiments due to safety reasons, and decided to create something approximating more grown up rocket designs. The result was a 3D-printed turbopump for fuel delivery.

The design is not dissimilar from a turbocharger in a car. On one side, a turbine wheel is turned by compressed air supplied from a tank or compressor. This turbine wheel is affixed to the same axle as an impeller which draws up fuel and pumps it out, ideally into a rocket’s combustion chamber. It’s all made out of resin-printed parts, which made creating the fine geometry of the turbine and impeller a cinch.

Running on compressed air at 80 psi, the turbopump is able to deliver 1.36L of water or rubbing alcohol fuel a minute. However, unfortunately, this first pass design can only deliver 20 psi of fuel pressure, which [Sciencish] suspects will not be enough to counteract combustion chamber pressures in his rocket design. More work is required to up this figure. Paired with a nozzle and ignition source, though, and it does make for some great flames.

Overall though, the safety benefit of this turbopump comes from the fact that the fuel is kept separate from the oxidizer until it reaches the combustion chamber. This comes with far less chance of fire or explosion versus a system that stores fuel pressurized by air.

While the design isn’t yet up to scratch for rocket use, it nonetheless works, and we suspect with some improvement to tolerances and fin design that the project should move along at a quick pace.

If solid rockets are more your thing though, we’ve featured plenty of those too. Video after the break.

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