We don’t get enough electrochemistry hacks on these pages, so here’s [Markus Bindhammer] of YouTube/Marb’s lab fame to give us a fix with their hand-built general-purpose electrochemistry device.

The basic structure is made from plyboard cut to size on a table saw and glued’n’screwed together. The top and front are constructed from an aluminium sheet bent to shape with a hand-bender. A laser-printed front panel finishes the aesthetic nicely, contrasting with the shiny aluminium. The electrode holders are part of off-the-shelf chemistry components, with the electrical contacts hand-made from components usually used for constructing stair handrails. Inside, a 500 RPM 12 V DC geared motor is mounted, driving a couple of small magnets. A PWM motor speed controller provides power. This allows a magnetic stirrer to be added for relevant applications. Power for the electrochemical cell is courtesy of a Zk-5KX buck-boost power supply with a range of 0 – 36 V at up to 5 A with both CV and CC modes. A third electrode holder is also provided as a reference electrode for voltammetry applications. A simple and effective build, we reckon!

Over the years, we’ve seen a few electrochemical hacks, like this DIY electroplating pen, a DIY electrochemical machining rig, and finally, a little something about 3D printing metal electrochemically.

youtube.com/embed/ZiB3p96-qc8?…

hackaday.com/2024/09/13/buildi…

The humble business card is usually a small slip of cardboard with some basic contact details on it — but as hackers know, it can be so much more. [Marian] has provided us a great example in the form of his own digital business card, which doubles as a handheld game!

Wanting to make his business card more interesting for better engagement, [Marian] was inspired by the Arduboy to give it some interactivity. He chose the STM32G030F6 microcontroller as a cheap and reliable option to run his business card. He then created a 10×9 LED matrix display using Charlieplexing to minimize the amount of I/O pins required. For controls, he went with the usual directional cross plus two action buttons. He implemented a variety of games on the card—including a Flappy Bird clone and a game similar to the classic Simon toy.

Files are on GitHub for the curious. We’ve featured some other great business cards this year, too. Indeed, we ran a whole challenge! If you’re cooking up your own exemplary little PCB to hand out at conferences, don’t hesitate to let us know!

hackaday.com/2024/09/13/2024-t…

When it comes to polarizing and confusing questions in electronics, wiring up shields is on the top-10 list when sorted by popularity. It’s a question most of us need to figure out at some point – when you place a USB socket symbol on your schematic, where do you wire up the SHIELD and MP pins?

Once you look it up, you will find Eevblog forum threads with dozens of conflicting replies, Stackexchange posts with seven different responses plus a few downvoted ones, none of them accepted, and if you try to consult the literature, the answer will invariably be “it depends”.

I’m not a connector-ground expert, I just do a fair bit of both reading and hacking. Still, I’ve been trying to figure out this debate, for a couple years now, re-reading the forum posts each time I started a new schematic with a yet-unfamiliar connector. Now, of course, coming to this question with my own bias, here’s a summary you can fall back on.

Consumer Ports

Putting HDMI on your board? First of all, good luck. Then, consider – do you have a reason to avoid connecting the shield? If not, certainly connect the shield to ground, use jumpers if that’s what makes you comfortable, though there’s a good argument that you should just connect directly, too. The reason is simple: a fair few HDMI cables omit GND pin connections, fully relying on the shield for return currents. When your HDMI connection misfires, you don’t want to be debugging your HDMI transmitter settings when the actual No Signal problem, as unintuitive as it sounds, will be simply your shield not being grounded – like BeagleBone and Odroid didn’t in the early days. By the way, is a DVI-D to HDMI adapter not working for you? Well, it might just be that it’s built in a cheap way and doesn’t connect the shields of the two sockets together – which is fixable.

Putting an Ethernet port on your board? This is the case where you should probably watch out, to make sure you understand what’s happening. Ethernet doesn’t use or need ground as such — it’s a galvanically isolated interface — but if you ground the shield and then use a shielded cable, your ground will go run along the shield. Do you need it? Likely not. Do you want it? I’d say it’s inconclusive. This only applies if your cable has a shield and metal-plated jacks that connect to it: while that’s not the norm, it’s the case for CAT6 and CAT7 cables, which are now pretty common because they’re pretty much required for 2.5 Gbps and above interfaces. Same goes for magjack shields, though watch out, they have a separate ground pin for the internal transformers and circuitry, you do need to wire that up, it won’t propagate any further than it might need to.

Every coaxial port that has a shield contact, but there’s only two contacts in total? This goes from RCA to BNC – the “shield” is actually often a ground pin, though not everyone might realize this. If it is used as a ground pin, passing the return current through, it has to stay grounded at both ends.

USB Ports

There are a fair few different USB port connectors and roles you could be putting on your board – here’s a quick answer for a somewhat common case. USB-A port that’s a host and therefore a power source? Connect the shield to ground. This is what you are universally expected to do, and something that indeed is done basically everywhere you look, bar devices that are being a bit bizarre.

What about a device port, like microUSB, or USB-B, or, hell, miniUSB? Well, the recommendation is leaving two footprints connected to the shield, so you can stuff them with 0-ohm resistors later, or put, say, a resistor-and-capacitor combo there if you’re having noise issues. Honestly, it is unlikely to hurt you if you ground it, doubly so if it’s a power only port – USB is a seriously sensitive interface when it comes to common mode shifts.

Using USB-C? Just wire the shield to ground. Do not pass go, do not collect 200, just wire it up to ground. Why? The specification requires you to, so that’s an easy call. It’s definitely true that, with dual-role ports being abundant, you can no longer really differentiate between host or device, so figuring out shield grounding based on already shaky roles would be a problem. By the way, this is a gift for all of us reverse-engineers out there – finally, a connector with a shield that is guaranteed to be ground-connected!

Not everyone realizes that the specification explicitly mandates it, and people still think separating shield from ground could be meaningful, including myself as recently as a few months ago. If anyone needs a pointer, tell them to check the USB-C cable and connector specification, revision 2.2. For sockets (receptacles), open page 44 and refer to the note 11, for plugs, open page 78 and refer to the note 6.

Other Concerns

There is some mechanical helpfulness to hard-wiring shield to ground, especially if you’re using copper fills without thermals. In my experience, it’s harder for connectors to break off when they have a plane of solid uninterrupted copper they adhere to! Now, thermals do help soldering a whole bunch, so I don’t want to be gung-ho about it, but if you’re dealing with a fully surface-mount connector that can get torn off, you might as well go thermal-less just this once. Worked for me on a larger-scale product of mine, to the point I completely stopped getting the problem where microUSB shield pads would get torn off the board. Of course, remember, microUSB with through-hole mounting pins is superiour mechanically – in case you do make the very situational decision to use microUSB.

The debate about grounding shields might never end, but if you want a summary, this is what I can say surefire, and I hope it helps. What’s your take?

hackaday.com/2024/09/13/where-…

It’s Friday the 13th, and despite having to dodge black cats and poorly located ladders, Elliot and Dan were able to get together and run down the best hacks of the first week of September. Our luck was pretty good, too, seeing how we stumbled upon a coffee table that walks your drink over to you on Strandbeest legs, a potato that takes passable photographs, and a cool LED display three times better than a boring old seven-segment.

If you’ve never heard of the Voynich manuscript, you’re in luck too, because we got a chance to look inside this medieval comic book literally, with multispectral analysis. Is your cruise ship too short? No worries, just lop it in two and add a section. Speaking of cutting things up, that’s what you need to do to see how your plus-size DIY rocket engine performed after test firing.

And finally, it was a sweep for Jenny this week with our “Can’t Miss” articles, where she both pines for a simpler, smaller web experience and wonders what the future holds for biomass fuels.

html5-player.libsyn.com/embed/…
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Download the zero-calorie MP3.

Episode 288 Show Notes:

News:

• Supercon 2024: Show Off Your Unique Display Tech
  
  • Hackaday Discord #badge-hacking

  
  

• Voyager 1 Completes Tricky Thruster Reconfiguration
• Orion Ceases Operations, Future Of Meade Unclear

What’s that Sound?

• Congratulations to [TechnoLibrarian] for recognizing the sound of a videotape loading.

Interesting Hacks of the Week:

• Mobile Coffee Table Uses Legs To Get Around
  
  • Move Over Strandbeest, Here’s Strider!
  • Mechanical Linkage CAD For Everyone
  • A Strandbeest Bicycle
  • Tin Spider Is 13-foot Rideable Strandbeest
  • Why Walking Tanks Never Became A Thing

  
  

• Hot Water Heater Hacked To Run On Solar Juice
• Using A Potato As Photographic Recording Surface
  
  • Use Blueprint Process To Print On Fabric With Lasers
  • Hackaday Prize Entry: A Printer For Alternative Photography

  
  

• Shedding New Light On The Voynich Manuscript With Multispectral Imaging
• Why Have Seven Segments When You Can Have 21?
  
  • Oh Brother, Would You Look At This Cistercian Clock
  • Supercon 2024: Show Off Your Unique Display Tech
  • AdvancedCalculator/Fonts at main · pedasmith/AdvancedCalculator · GitHub
  • Segmented display designs
  • Custom Multi-Segment E-Ink Displays From Design To Driving

  
  

• A Look Inside A DIY Rocket Motor

Quick Hacks:

• Elliot’s Picks
  
  • Inkycal Makes Short Work Of E-Paper Dashboards
  • Microsoft Sculpt Keyboard Lives Again With RP2040
  • Cruise Ship-Lengthening Surgery: All The Cool Companies Are Doing It

  
  

• Dan’s Picks:
  
  • The Apple Watch As An Ammeter
  • The Science Of Coating Steel
  • Glowing Egg Is A One-Oeuf Solution For Tracking Cycles

  
  

Can’t-Miss Articles:

• A Look At The Small Web, Part 1
  
  • Gopher (protocol) – Wikipedia

  
  

• If Wood Isn’t The Biomass Answer, What Is?

hackaday.com/2024/09/13/hackad…

There’s a good chance you’ve seen “Nixie clocks” on the Internet that replace the classic cold cathode tubes with similarly sized LCD panels. The hook is that the LCDs can show pictures and animations of Nixie tubes — or pretty much anything else for that matter — to recreate the look of the real thing, while being far cheaper and easier to produce. It’s a hack for sure, and that’s the way we like it.

[Trung Tran] liked the idea, but didn’t just want to buy a turn-key clock. So he’s decided to build his own version based on the ESP32-S3. The WiFi-enabled microcontroller syncs up to the latest time via NTP, then uses a PCF8563 real-time clock (RTC) module to keep from drifting too far off the mark. The six displays, which plug into the custom PCB backplane, can then show the appropriate digits for the time. Since they’re showing image files, you can use any sort of font or style you wish. Or you could show something else entirely — the demo video below shows off each panel running the Matrix “digital rain” effect.

Unfortunately, [Trung Tran] hasn’t shared a whole lot of technical info about this project yet. But between the Open Source Hardware logo on the PCB, and the fact that project page says “Part 1” at the top, we’re hopeful that more information is forthcoming.

We first saw the commercial version of this concept back in 2021, and had to admit, it was a pretty cool idea. It’s good to see the community creating their own versions, and if they end up being open hardware so that others can reproduce and improve the design, even better.

hackaday.com/2024/09/13/recrea…

I sette pezzi del disco riflettono l'immagine sonora di un gruppo che ha raggiunto un livello compositivo molto alto, la perfetta fusione di luce e tenebre, di vita e morte, di cosmo e terra, contrari che si girano su loro stessi.

@Musica Agorà

iyezine.com/jordaan-season-of-…

Jordaan - Season of redemption

Jordaan - Season of redemption - Jordaan - Season of redemption: I sette pezzi del disco riflettono l'immagine sonora di un gruppo che ha raggiunto un livello compositivo molto alto. - Jordaan

^{Massimo Argo (In Your Eyes ezine)}

Il trio di Düsseldorf (composto dal frontman e chitarrista Christian "Doctor" Koch, coadiuvato da Dario Treese al basso e tastiere e Frank Matenaar alla batteria) non lascia nulla al caso, curando ogni release con particolari artwork che si richiamano all'iconografia della cultura psichedelica/hippie e rievocano i manifesti-poster dei concerti acid/blues/psych/space rock dei Sixties (anche dando vita a festival pysch)....

@Musica Agorà

iyezine.com/vibravoid-we-canno…

VIBRAVOID - WE CANNOT AWAKE

VIBRAVOID - WE CANNOT AWAKE - Bene (si fa per dire) dopo questo pippone introduttivo, converrete sul fatto che in quel tipo di contesto "musicale", tossico per l'udito e nocivo per l'anima, sicuramente non ascolterete mai i Vibravoid, prolifica band …

^{Reverend Shit-Man (In Your Eyes ezine)}

Ventottesimo (!!!) album per gli OSEES, la creatura multiforme - con varie declinazioni nel moniker - guidata del prolifico talento di John Dwyer, da sempre anima del progetto e frontman polistrumentista dotato di una creatività artistica preossoché inesauribile.

@Musica Agorà

iyezine.com/osees-sorcs-80

OSEES - SORCS 80

OSEES - SORCS 80 - Ventottesimo (!!!) album per gli OSEES, la creatura multiforme - con varie declinazioni nel moniker - guidata del prolifico talento di John Dwyer, da sempre anima del progetto e frontman polistrumentista dotato di una creatività ar…

^{Reverend Shit-Man (In Your Eyes ezine)}

Gli Haji mi mandano il loro disco chiedendomi di essere estremamente sincero nel parlarne, la frase esatta è "di', se lo pensi, che è una cagata pazzesca".

@Musica Agorà

iyezine.com/haji-lexotan-sailo…

Haji - Lexotan Sailors 

Haji - Lexotan Sailors  - Quindi carissimi Haji il vostro disco non è affatto una cagata pazzesca, vi conosco e so quanto siate bravi e motivati, è anzi pregno di energia e di attitudine, distorsioni in libertà e drammaticità in abbondanza. - Haji

^{Il Santo (In Your Eyes ezine)}

"se non si è ancora effettuato il check-in, è ammesso il cambio data e ora fino alle 23:59 del giorno precedente la data del viaggio, salvo diverse disposizioni regionali;

se non si è ancora effettuato il check-in, è ammesso il cambio ora fino alle 23:59 del giorno del viaggio, salvo diverse disposizioni regionali;"

da lefrecce.it/Channels.Website.W…
…confesso che ci ho messo unpo' a trovare la differenza

Post scriptum. Secondo il "Corriere Fiorentino" Cinzia Dal Pino aveva passato la serata in un posto dove cuociono pesci e li vendono a prezzi molto alti.
Siccome pioveva, le avevano prestato un ombrello.
Dopo aver recuperato la pochette, Cinzia è tornata a restituirlo.
Un senso della cortesia e delle priorità che rivela un mondo intero.