A Number Of Microphones… Er, Inductors, Rather

There’s a famous old story about [Charles Steinmetz] fixing a generator for [Henry Ford]. He charged a lot of money for putting a chalk X in the spot that needed repair. When [Ford] asked for an itemization, the bill read $1 for the chalk, and the balance for knowing where to draw the X. With today’s PCB layout tools, it seems easy to put components down on a board. But, as [Kasyan TV] points out in the video below, you still have to know where to put them.

The subject components are inductors, which are particularly picky about placement, especially if you have multiple inductors. After all, inductors affect one another — that’s how transformers work. So there are definite rules about good and bad ways to put a few inductors on a board.

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BhangmeterV2 Answers The Question “Has A Nuke Gone Off?”

You might think that a nuclear explosion is not something you need a detector for, but clearly not everyone agrees. [Bigcrimping] has not only built one, the BhangmeterV2, but he has its output publicly posted at hasanukegoneoff.com, in case you can’t go through your day without checking if someone has nuked Wiltshire.

The Bhangmeter is based on an off-the-shelf “nuclear event detector”, the HSN-1000L by Power Device Corporation.

The HSN 1000 Nuclear Event Detector at the heart of the build. We didn’t know this thing existed, never mind that it was still available.

Interfacing to the HSN-1000L is very easy: you give it power, and it gives you a pin that stays HIGH unless it detects the characteristic gamma ray pulse of a nuclear event. The gamma ray pulse occurs at the beginning of a “nuclear event” precedes the EMP by some microseconds, and the blast wave by perhaps many seconds, so the HSN-1000 series seems be aimed at triggering an automatic shutdown that might help preserve electronics in the event of a nuclear exchange.

[Bigcrimping] has wired the HSN-1000L to a Raspberry Pi Pico 2 W to create the BhangmeterV2. In the event of a nuclear explosion, it will log the time the nuclear event detector’s pin goes low, and the JSON log is pushed to the cloud, hopefully to a remote server that won’t be vaporized or bricked-by-EMP along with the BhangmeterV2. Since it is only detecting the gamma ray pulse, the BhangmeterV2 is only sensitive to nuclear events within line-of-sight, which is really not where you want to be relative to a nuclear event. Perhaps V3 will include other detection methods– maybe even a 3D-printed neutrino detector?

If you survive the blast this project is designed to detect, you might need a radiation detector to deal with the fallout. For identifying exactly what radionuclide contamination is present, you might want a gamma-ray spectrometer.

It’s a sad comment on the modern world that this hack feels both cold-war vintage and relevant again today. Thanks to [Tom] for the tip; if you have any projects you want to share, we’d love to hear from you whether they’d help us survive nuclear war or not.

Split Keyboard Uses No PCB

When [daniely101] wanted a split keyboard, he decided to build his own. It wound up costing $25 to create a wireless board with no custom PCB required. Each half has its own microcontroller, and the whole thing connects via Bluetooth. While we don’t mind making a PCB, we can appreciate that you could change your mind easily with this wiring scheme.

The 3D printed case holds the keys, and then it is just a matter of carefully soldering the keys to the microcontrollers. Of course, each side also has to have its own battery. The ZMK firmware is split in half, one part for each side of the keyboard. The nRF52840 CPUs have plenty of wireless connectivity. The keys are set in rows and columns, so the amount of soldering back to the controller is manageable.

While we applaud the wireless design, it does seem odd that you have to charge both halves and turn them on and off separately. But that’s the nice thing about a design like this — you could modify the design to not have a split. Or, you could allow one flexible wire pair to run across for power. Of course, you could modify the layout, including adding or deleting keys.

You might consider adding a pointing device. At least you don’t have to pull out a saw.

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ZPUI Could Be Your Tiny Embedded GUI

One of the most frustrating things to me is looking at a freshly-flashed and just powered up single board computer. My goal with them is always getting to a shell – installing packages, driving GPIOs, testing my proof of concept code, adjusting the device tree to load peripheral drivers. Before I can do any of that, I need shell access, and getting there can be a real hassle.

Time after time, I’ve struggled trying to get to a shell on an SBC. For best results, you’d want to get yourself a keyboard, monitor, and an Ethernet cable. Don’t have those, or there’s no space to place them? Maybe a UART connection will work for you – unless it’s broken or misconfigured. Check your pinouts twice. Sure, nowadays you can put WiFi credentials into a text file in /boot/ – but good luck figuring out the IP address, or debugging any mistakes you might make formatting the file. Nowadays, Pi 4 and 5 expose a USB gadget connection on the USB-C port, and that helps… unless you’re already powering the Pi from that port. There’s really no shortage of failure modes here.

If you put a Pi on your network and it goes offline, you generally just don’t know what happened unless you reboot it, which can make debugging into a living hell. I’ve dealt with single-board computers mounted above fiberglass lifted ceilings, fleets of Pi boards at workshops I organized, pocket-carried Pi boards, and at some point, I got tired of it all. A hacker-aimed computer is meant to be accessible, not painful.

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ESP32 Dashboard Is A Great Way To Stay Informed

The original ESP32 may be a little long in the tooth by now, but it remains a potent tool for connected devices. We were drawn to [Max Pflaum]’s ESP32 Dashboard as a great example, it’s an ESP32 hooked up to an e-paper display. The hardware is simple enough, but the software is what makes it interesting.

This is deigned as a configurable notification tool, so to make it bend to the user’s will a series of widgets can be loaded onto it. The device runs MicroPython, making it easy enough to write more than the ones already on place. The screen is divided into four zones, allowing for a range of widgets to be used at once. All the details can be found in a GitHub repository.

We like it for its configurability and ease of programming, and because it delivers well on the promise of a useful device. An ESP32 and e-ink combination with MicroPython apps is something we’ve seen before in the world of badges.

Just For Laughs: Charlie Douglass And The Laugh Track

I ran into an old episode of Hogan’s Heroes the other day that stuck me as odd. It didn’t have a laugh track. Ironically, the show was one where two pilots were shown, one with and one without a laugh track. The resulting data ensured future shows would have fake laughter. This wasn’t the pilot, though, so I think it was just an error on the part of the streaming service.

However, it was very odd. Many of the jokes didn’t come off as funny without the laugh track. Many of them came off as cruel. That got me to thinking about how they had to put laughter in these shows to begin with. I had my suspicions, but was I way off!

Well, to be honest, my suspicions were well-founded if you go back far enough. Bing Crosby was tired of running two live broadcasts, one for each coast, so he invested in tape recording, using German recorders Jack Mullin had brought back after World War II. Apparently, one week, Crosby’s guest was a comic named Bob Burns. He told some off-color stories, and the audience was howling. Of course, none of that would make it on the air in those days. But they saved the recording.

A few weeks later, either a bit of the show wasn’t as funny or the audience was in a bad mood. So they spliced in some of the laughs from the Burns performance. You could guess that would happen, and that’s the apparent birth of the laugh track. But that method didn’t last long before someone — Charley Douglass — came up with something better. Continue reading “Just For Laughs: Charlie Douglass And The Laugh Track”