Vectorscope KiCad Redrawing Project

November 13, 2023 by 23 Comments

When I saw this year’s Supercon Vectorscope badge, I decided that I had to build one for myself. Since I couldn’t attend in-person, I immediately got the PCBs and parts on order. Noting that the GitHub repository only had the KiCad PCB file and not the associated schematics and project file, I assumed this was because everyone was in a rush during the days leading up to Supercon weekend. I later learned, however, that there really wasn’t a KiCad project — the original design was done in Circuit Maker and the PCB was converted into KiCad. I thought, “how hard can this be?” and decided to try my hand at completing the KiCad project.

Fortunately I didn’t have to start from scratch. The PCB schematics were provided, although only as image files. They are nicely laid out and fortunately don’t suffer the scourge of many schematics these days — “visual net lists” that are neither good schematics nor useful net lists. To the contrary, these schematics, while having a slightly unorthodox top to bottom flow, are an example of good schematic design. Continue reading “Vectorscope KiCad Redrawing Project” →

Watch Time Roll By On This Strange, Spiral Clock

November 13, 2023 by 15 Comments

[Build Some Stuff] created an unusual spiral clock that’s almost entirely made from laser-cut wood, even the curved and bendy parts.

The living hinge is one thing, but getting the spacing, gearing, and numbers right also takes work.

The clock works by using a stepper motor and gear to rotate the clock’s face, which consists of a large dial with a spiral structure. Upon this spiral ramp rolls a ball, whose position relative to the printed numbers indicates the time. Each number is an hour, so if the ball is halfway between six and seven, it’s 6:30. At the center of the spiral is a hole, which drops the ball back down to the twelve at the beginning of the spiral so the cycle can repeat.

The video (embedded below) demonstrates the design elements and construction of the clock in greater detail, and of particular interest is how the curved wall of the spiral structure consists of a big living hinge, a way to allow mostly rigid materials to flex far beyond what they are used to. Laser cutting is well-suited to creating living hinges, but it’s a technique applicable to 3D printing, as well.

Thanks to [Kelton] for the tip!

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JawnCon 0x0: A Strong Start With A Bright Future

November 13, 2023 by 9 Comments

Last month, I had the pleasure witnessing a birth. No, not of a child. What I’m talking about is something far rarer, though arguably, just as loud and danger fraught — the birth of a new hacker convention.

The very first JawnCon took place on October 19th and 20th at Arcadia University, just outside of Philadelphia. If you’re in the Northeast US and suddenly find yourself surprised to learn that a hacker con managed to slip under your radar, don’t be. The organizers, who previously helped launch the WOPR Summit back in 2019, wisely decided to keep the scale of this first outing in check. Just a single track of talks, a chill out room, and 130 or like-minded individuals.

Although, even if they’d hatched a more ambitious plan, it’s hard to imagine they’d have had enough time to pull it off. Due to various circumstances, JawnCon had to come together at a breakneck pace, with less than 100 days separating the con’s inception and kickoff. That an event such as this could not only be organized so quickly, but go off without a hitch, is a testament to the incredible folks behind the scenes.

As for what a Jawn is…well, that might take a bit more explaining. It’s regional slang that’s perhaps best described as a universal noun in that it can be used to refer to basically anything or anyone. Think “smurf” or “da kine”. According to organizer Russell Handorf, the all-encompassing nature of the word describes not only his personal ethos but the spirit of the event. Rather than focusing too closely on any one aspect of hacking, JawnCon set out to explore a diverse array of tech topics from both the new and old schools. It would be an event where you could listen to a talk on payphone remote management, try your hand at lock picking, and learn about the latest in anti-drone technology, all under the same roof.

To that end, the team did an incredible job. Everyone I spoke to, young or old, newbie or vet, had a fantastic time. What’s more, as revealed in the Closing Remarks, the con actually managed to stay in the black — no mean feat for a first attempt. With a little luck, it seems like JawnCon is well on its way to becoming one of the Northeast’s can’t-miss hacker events. Continue reading “JawnCon 0x0: A Strong Start With A Bright Future” →

Stream Vinyl To Your Sonos Without The Financial Penalty

November 13, 2023 by 47 Comments

One of the unexpected success stories in the world of hi-fi over the past decade has been the resurgence of the vinyl LP as a musical format. What was once old hat is now cool again, but for freshy minted vinyl fans there’s a snag. Hi-fi itself has moved on from the analogue into the digital, so what can be done if your listening comes through a Sonos system. Sonos will sell you a box to do that of course, but it’s as overpriced as 2023-pressing vinyl. [Max Fischer] has a far better solution, in the form of a Raspberry Pi loaded with open source software.

At the vinyl end is a Behringer audio interface containing a pre-amp with the required RIAA response curve. This acts as the source for the DarkIce audio streamer and the IceCast2 media serer, all of which even with the cost of a Pi and the interface, is considerably less than the commercial device.

We’re guessing that a more humble interface coupled to an older RIAA pre-amp could cut the cost further, and we’d be hugely curious as to whether a simple mic pre-amp could be used alongside some DSP from the likes of Gnu Radio to give the RIAA response.

Either way, he’s made a handy device for any 21st-century vinyl fan. Meanwhile if you’re one of the streaming generation seduced by round plastic discs, we’ve gone into some detail about their audiophile credentials in the past. And if you have found yourself a turntable, of course you’ll need to know how to set it up properly.

General Instruments Video Game Chip Rides Again

November 13, 2023 by 17 Comments

Early video games like Pong were not computer-controlled. They used discrete logic to generate the TV signals. As you might expect, the market exploded when you could get all the logic on a chip. Many of those games used the General Instrument AY-3-8500-1 chip, and [Jeff Tranter] shows us the chip and the many different yet similar games it could play. You can check out the retro gameplay in the video below.

These were marvels of their day, although, by today’s standards, they are snoozers. All the games were variations on a theme. A ball moved and hit paddles, walls, or goals. A few available light gun games were rarely seen in the wild because they took extra components.

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A Small-Packing Antenna For 2 Metre Portable Work

November 12, 2023 by 15 Comments

One of amateur radio’s many interests comes in portable operation, taking your radio to an out of the way place, usually a summit, and working the world using only what can be carried in. Often this means using the HF or shortwave bands, but the higher frequencies get a look-in as well. A smaller antenna is no less the challenge when it comes to designing one that can be carried though, and [Thomas Witherspoon] demonstrates this with a foldable loop antenna for the 2 metre band.

The antenna provides a reminder that the higher bands are nothing to be scared of in construction terms, it uses a BNC-to-4 mm socket adapter as its feedpoint, and makes the rectangular shape of the loop with pieces of fiberglass tube. The wire itself is flexible antenna wire, though we’re guessing almost any conductor could be used. The result is a basic but useful antenna that certainly packs down to a very small size, and we can see it would be a useful addition to any portable operator’s arsenal.

If you’re a 2 metre band user, this certainly isn’t the first time we’ve visited lightweight antennas for this band.

Data Science The Stanford Way

November 12, 2023 by 27 Comments

Data science is a relatively new term for a relatively old discipline. Essentially, it is data analysis, particularly for large data sets. It involves techniques as wide-ranging as statistics, computer science, and information theory. What to know more? Stanford has a “Data Science Handbook” that you can read online.

Topics range from how to design a study and create an analytic plan to how to do data visualization, summarization, and analysis. The document covers quite a bit but is very concise.

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