A Network Attached Radiation Monitor

It started as a joke, as sometimes these things do. [Marek Więcek] thought building a personal radiation detector would not only give him something to work on, but it would be like having a gadget out of the Fallout games. He would check the data from time to time and have a bit of a laugh. But then things got real. When he started seeing rumors on social media that a nearby nuclear reactor had suffered some kind of radiation leak, his “joke” radiation detector suddenly became serious business.

With the realization that having his own source of detailed environmental data might not be such a bad idea after all, [Marek] has developed a more refined version of his original detector (Google Translate). This small device includes a Geiger counter as well as sensors for more mundane data points such as temperature and barometric pressure. Since it’s intended to be a stationary monitoring device, he even designed it to be directly plugged into an Ethernet network so that it can be polled over TCP/IP.

[Marek] based the design around a Soviet-era STS-5 Geiger tube, and outfitted his board with the high voltage electronics to provide it with the required 400 volts. Temperature, barometric pressure, and humidity are read with the popular Bosch BME280 sensor. If there’s no Ethernet network available, data from the sensors can be stored on either the built-in SPI flash chip or a standard USB flash drive.

The monitor is powered by a PIC32MX270F256B microcontroller with an Ethernet interface provided by the ENC28J60 chip. In practice, [Marek] has a central Raspberry Pi that’s polling the monitors over the network and collecting their data and putting it into a web-based dashboard. He’s happy with this setup, but mentions he has plans to add an LCD display to the board so the values can be read directly off of the device. He also says that a future version might add WiFi for easier deployment in remote areas.

Over the years we’ve seen a fair number of radiation monitors, from solar-powered WiFi-connected units to the incredible work [Radu Motisan] has done building his global network of radiation detectors. It seems hackers would rather not take somebody else’s word for it when it comes to the dangers of radiation.

Putting An Out Of Work IPod Display To Good Use

[Mike Harrison] produces so much quality content that sometimes excellent material slips through the editorial cracks. This time we noticed that one such lost gem was [Mike]’s reverse engineering of the 6th generation iPod Nano display from 2013, as caught when the also prolific [Greg Davill] used one on a recent board. Despite the march of progress in mobile device displays, small screens which are easy to connect to hobbyist style devices are still typically fairly low quality. It’s easy to find fancier displays as salvage but interfacing with them electrically can be brutal, never mind the reverse engineering required to figure out what signal goes where. Suffice to say you probably won’t find a manufacturer data sheet, and it won’t conveniently speak SPI or I2C.

After a few generations of strange form factor exploration Apple has all but abandoned the stand-alone portable media player market; witness the sole surviving member of that once mighty species, the woefully outdated iPod Touch. Luckily thanks to vibrant sales, replacement parts for the little square sixth generation Nano are still inexpensive and easily available. If only there was a convenient interface this would be a great source of comparatively very high quality displays. Enter [Mike].

Outer edge of FPGA and circuit

This particular display speaks a protocol called DSI over a low voltage differential MIPI interface, which is a common combination which is still used to drive big, rich, modern displays. The specifications are somewhat available…if you’re an employee of a company who is a member of the working group that standardizes them — there are membership discounts for companies with yearly revenue below $250 million, and dues are thousands of dollars a quarter.

Fortunately for us, after some experiments [Mike] figured out enough of the command set and signaling to generate easily reproduced schematics and references for the data packets, checksums, etc. The project page has a smattering of information, but the circuit includes some unusual provisions to adjust signal levels and other goodies so try watching the videos for a great explanation of what’s going on and why. At the time [Mike] was using an FPGA to drive the display and that’s certainly only gotten cheaper and easier, but we suspect that his suggestion about using a fast micro and clever tricks would work well too.

It turns out we made incidental mention of this display when covering [Mike]’s tiny thermal imager but it hasn’t turned up much since them. As always, thanks for the accidental tip [Greg]! We’re waiting to see the final result of your experiments with this.

Kinematic Mount For 3D Printer Bed Shows Practical Design

Aluminum bed with new kinematic mount and base on printer Son of Megamax, at the Milwaukee Makerspace

[Mark Rehorst] has been busy designing and building 3D printers, and Son of Megamax — one of his earlier builds — needed a bed heater replacement. He took the opportunity to add a Kelvin-type kinematic mount as well. The kinematic mount and base efficiently constrain the bed in a controlled way while allowing for thermal expansion, providing a stable platform that also allows for removal and repeatable re-positioning.

After a short discussion regarding the heater replacement, [Mark] explains the design and manufacture of his kinematic mount. Of particular note are the practical considerations of the design; [Mark] aimed to use square aluminum tubing as much as possible, with machining requirements that were easily done with the equipment he had available. Time is a resource after all, and design decisions that help one get something working quickly have a value all their own.

If you’re still a bit foggy on kinematic mounts and how they work, you’re not alone. Check out our coverage of this 3D-printed kinematic camera mount which should make the concept a bit clearer.

Voja Antonic: Designing The Cube

Voja Antonic designed this fantastic retrocomputing badge for Hackaday Belgrade in 2018, and it was so much fun that we wanted to bring it stateside to the Supercon essentially unaltered. And that meant that Voja had some free time to devote to a new hardware giveaway: the Cube. So while his talk at Supercon in November was ostensibly about the badge, he just couldn’t help but tell us about his newer love, and some of the extremely clever features hidden within.

It’s funny how the hardware we design can sometimes reflect so much on the creator. Voja designed then-Yugoslavia’s first widely used home computer (and published the DIY plans in a magazine!). Thousands were built from their kits. The Galaksija was a Z80-based design with a custom BASIC that was just barely squeezed into the available 4K of ROM. So you shouldn’t be shocked that the retro-badge has a working keyboard and a nice BASIC on board.

But let’s jump ahead to the Cube, because that’s even more of a passion project. On the outside, they’re very simple devices, with only a USB port and a sweet diffused LED ring visible. Aesthetic? Minimalistic? Beautiful, honestly.
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Yell At Your Desk To Get Up In The Morning

Standing desks are great conversation starters in the office – whether you like it or not. How do you know someone’s got a standing desk? Don’t worry, they’ll tell you. Standing desks have their benefits, but for maximum flexibility, many people choose a desk that can raise and lower depending on their needs. [Wassim] had just such a desk, but found pushing the buttons too 20th century for his tastes. Naturally, Google Assistant integration was the key here.

[Wassim] started out intending to capture and then spoof the desk controller’s signals to the motors, before realising it was likely easier to simply spoof button presses instead. This was achieved through a handful of NPN transistors and an Onion Omega2+ microcontroller board. Then it was a simple case of coding the controller to press the various buttons in response to HTTP requests received over WiFi. Google Assistant integration was then handled with IFTTT, though [Wassim] also discusses the possibility of implementing the full Smart Home API.

It’s entertaining to watch [Wassim] issue commands and have the desk slowly rise in response. Of course, there are other approaches, like this sneaky use of PVC to hack the office furniture.

https://medium.com/@wassimchegham/hey-google-set-my-desk-to-standing-mode-b21dcc40d4b5

How To Deal With A Cheap Spectrum Analyzer

The Hackaday Superconference is all about showcasing the hardware heroics of the Hackaday community. We also have a peer-reviewed journal with the same goal, and for the 2018 Hackaday Superconference we got a taste of the first paper to make it into our fully Open Access Journal. It comes from Ted Yapo, it is indeed a tale of hardware heroics: what happens when you don’t want to spend sixty thousand dollars on a vector network analyzer?

Ted’s talk begins with a need for a network analyzer. These allow for RF measurements, but if you ever need one, be prepared: you can spend twenty thousand dollars on a used VNA. Around the time Ted’s project began, Rigol released their cheap spectrum analyzer, the DSA815. This thing only cost a thousand dollars. It was their first revision of the hardware, and it was only a scalar network analyzer. Being the first revision of the hardware, there were a few problems; there was leakage that would affect the measurement. The noise floor was higher than it should have been. These problems can be corrected, though, with a little bit of cunning from Ted:

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New Part Day: Small, Cheap, And Good LIDAR Modules

Fully autonomous cars might never pan out, but in the meantime we’re getting some really cool hardware designed for robotic taxicab prototypes. This is the Livox Mid-40 Lidar, a LIDAR module you can put on your car or drone. The best part? It only costs $600 USD.

The Livox Mid-40 and Mid-100 are two modules released by Livox, and the specs are impressive: the Mid-40 is able to scan 100,000 points per second at a detection range of 90 m with objects of 10% reflectivity. The Mid-40 sensor weighs 710 grams and comes in a package that is only 88 mm x 69 mm x 76 mm. The Mid-100 is basically the guts of three Mid-40 sensors stuffed into a larger enclosure, capable of 300,000 points per second, with a FOV of 98.4° by 38.4°.

The use case for these sensors is autonomous cars, (large) drones, search and rescue, and high-precision mapping. These units are a bit too large for a skateboard-sized DIY Robot Car, but a single Livox Mid-40 sensor, pointed downward on a reasonably sized drone could perform aerial mapping

There is one downside to the Livox Mid sensors — while you can buy them direct from the DJI web site, they’re not in production. These sensors are only, ‘Mass-Production ready’. This might be just Livox testing the market before ramping up production, a thinly-veiled press release, or something else entirely. That said, you can now buy a relatively cheap LIDAR module that’s actually really good.