You’ve spent months developing your product, your Kickstarter just finished successfully, and now you’re ready to order all the parts. Unfortunately, your main component, an ATmega328P, is out of stock everywhere with a manufacturer lead time of 16 weeks. Now what?
When manufacturing things in large volumes, acquiring enough stock at the right time can be tricky. There can be seasonal shortages with companies trying to get products manufactured and available for Christmas. There can be natural disasters like floods of hard drive factories, or politically-related availability problems like tantalum for capacitors, or maybe new markets open up that increase demand or a new product sucks up all the available supply. The result is all the same; you have a harder time getting what you need. Fortunately, there are some ways to avoid this problem, or at least mitigate it.
When it comes to microcontroller development boards, we have a plethora of choices at our disposal. Each has its strengths and weaknesses, be they associated with its support and community, its interface capabilities, or its choice of processor family. Most boards you’ll find in our communities come from niche manufacturers, or at least from manufacturers who started as such. Just occasionally though along comes one whose manufacturer you will have heard of, even whose manufacturer the Man in the Street will have heard of.
Which brings us neatly to today’s story, the quiet announcement from Sony, of a new microcontroller development board called the Spritzer. This is Arduino compatible in both physical footprint and IDE, is intended for IoT applications, and packs GPS, an audio codec, and an ARMCortexM4 at 156 MHz. There is a Japanese page with a little more detail (Google Translate link), on which they talk about applications including audio beam forming with up to eight microphones, and a camera interface.
The board is due to be available sometime early next year, and while it looks as though it will be an interesting device we’d sound a note of caution to Sony. It is not good enough to have an amazing piece of hardware; the software and community support must be more than just make-believe. If they can crack that then they might just have a winner on their hands, if they fail to make any effort then they will inevitably follow Intel into the graveyard of also-ran boards.
I’m working on a project involving the need to precisely move a tool based on the measured distance to an object. Okay, yeah, it’s a CNC mill. Anyway, I’d heard of time of fight sensors and decided to get one to test out, but also to be thorough I wanted to include other distance sensors as well: a Sharp digital distance sensor as well as a more sophisticated proximity/light sensor. I plugged them all into a breadboard and ran them through their paces, using a frame built from aluminum beams as a way of holding the target materials at a specific height.
On the hardware side, the first prototype radar horn was made out of cardboard with aluminum foil taped around it. With the concept proven, [JBeale] made a second horn out of thin copper-clad sheets, but reports that the performance is just about the same. The other hardware hack was simply to tack a wire on the radar module’s analog output and add a simple op-amp gain stage, which extended the sensing range well beyond the ten feet or so that these things are usually used for.
With all that signal coming in, [JBeale] separates out the noise by taking an FFT of the Doppler frequency-shift signal. Figuring that people walk around 2.2 miles per hour, [JBeale] focuses on the corresponding 70 Hz frequency bin and finds that the radar will detect people out to 80 feet. Wow!
This trick of taking an el-cheapo radar unit and amplifying the signal to do something useful isn’t new to Hackaday. [Mathieu] did it with the very same HB-100 unit way back in 2013, and then again with a more modern CDM324 model. But [JBeale]’s hacked horn and clever backend processing push out the limits of what you can expect to do with these cheap units. Kudos.
Everyone knows how to convert from Celsius to Fahrenheit, right? On a digital thermometer you just flick the little switch, on a weather app you change the settings, or if worse comes to worse, you let Google do the math for you. But what if you want to solve the problem the old-fashioned way? Then you pull out a few op amps and do your conversions analog style.
We’ve seen before how simple op amp circuits can do basic math, and the equation that [Kerry Wong] wants to solve is even simpler. Recalling the old Tf = 9/5·Tc + 32 formula (and putting aside the relative merits of metric versus traditional units; we’ve had enough of that argument already), [Kerry] walks us through a simple dual op amp circuit to convert the 1 mV/°C output of a thermocouple module to 1 mV/°F. The scaling is taken care of by a non-inverting amplifier with resistors chosen to provide a gain of 1.8, while the offset is handled by a differential amplifier that adds 32 mV to the scaled input. Strategically placed trimmers allow [Kerry] to tweak the circuit to give just the right conversion.
For jobs like this, it’s tempting to just use an analog input on an Arduino and take care of conversions in code. But it’s nice to know how to do it old school, too, and hats off to [Kerry] for showing us the details.
[Pete] wondered how real-time clock modules could be selling on eBay for $1.50 when the main component, the Maxim DS3231 RTC/TCXO chip, cost him more like $4 apiece. Could the cheap modules contain counterfeit chips?
Well, sure they could. But in this case, they didn’t, and [Pete] has the die shots to prove it. He started off by clipping the SOIC leads rather than desoldering — he’s not going to be reusing this chip after he’s cut it in half. Next was a stage of embrittling the case by heating it up with a lighter and dunking it in water. Then he went at it with sandpaper.
It’s cool. You can see the watch crystal inside, and all of the circuitry. The DS3231 includes a TCXO — temperature-corrected crystal oscillator — and it seems to have a bank of capacitors that it connects and disconnects depending on the chip’s temperature to keep the oscillator running at the right speed. [Pete] used one in an offline situation, and it only lost sixteen seconds over a year, so we’d say that they work fine.
At this point, it’s not really correct to describe DEF CON as a single, gigantic conference for security, tech, and other ‘hacky’ activities. DEF CON is more of a collection of groups hosting villages, get-togethers, meetups, and parties where like-minded individuals share their time, company, electronic war stories, and whiskey. One of the largest groups measured by the number of rideable, inflatable unicorns is Queercon, a ‘conference within a conference’ dedicated to LGBT causes, a rager of a party, and a killer conference badge.
The Queercon badge is always a work of art, and this year is no exception. Last year, we took a look at an immaculate squid/cuttlefish badge, and a few years before that, the Queercon badge was a beautiful 3.5″ floppy embedded with far too many RGB LEDs. This year’s Queercon badge was equally as amazing, quite literally pushing badgecraft into another dimension. The folks behind the Queercon badge just wrote up their postmortem on the badge, and it’s an excellent example of how to push PCBs into the space of human interaction.
The development of the 2017 Queercon badge had a really tough act to follow. Last year’s Blooper squid/cuttlefish badge is a high point in the world of functional PCB art, and by January of this year, the team didn’t know where to take badgecraft next.
In the end, the QC badge team decided on a ‘failsafe’ design — it wasn’t necessarily going to be the best idea, but the design would minimize risk and development time.
A single 2017 Queercon badge
The two obvious features of this badge are an incredible number of tiny RGB LEDs, and very strange hermaphroditic edge connectors, allowing these badges to be plugged together into a panel of badges or a cube. What does this badge do? It blinks. If you have five friends, you can make something that looks like the Companion Cube from Portal.
Hardware
The killer feature for this badge is a vast array of RGB LEDs. Instead of going with WS2812s or APA101s, the Queercon badge team found simple, 0604 RGB LEDs, priced at about $0.026 a piece. There are 73 LEDs in total, all driven by the same TI LED driver used in previous years, combined with two shift registers and 15 FETs to control the LED commons. Although the LED driver is able to address all 219, and even though the badge is powered by a 32-bit ARM Cortex M3 microcontroller, this is pretty much the limit of how many LEDs can be controlled with this setup.
The Queercon badge always has a bit of interconnectedness built in, and this year is no exception. This year the badge uses a strange universal connector mounted along the four sides of the badge. When one badge is plugged into the other, they mate producing a ‘fabric’ of glowing badges. The range of motion on this connector allows for 180 degrees of rotation, but surprisingly most Queercon badge holders only assembled single planes of badges. It took a bit of cajoling from the badgemakers to get people to assemble a cube, and no other weird shapes were constructed out of multiple badges. If anyone likes this idea of interconnected badges, I would like to personally suggest equilateral triangles — this would allow for icosahedrons or hexagon-based solids.
A Game
A badge wouldn’t be complete without a game, and the Queercon badge has it in spades. The UI/UX/graphics designer [Jonathan] came up with a game loosely based on a game called ‘Alchemy’. Every badge comes loaded with a set of basic elements (air, fire, water, earth), represented as pixel art on the 7×7 RGB LED matrix. Combining these elements leads to even more elements — water plus fire equals beer, for example. Think of it as crafting in Minecraft, but with badges.
Starbucks was responsible for sponsoring a portion of Queercon this year, so ten special badges were loaded up with a fifth element: coffee. Elements derived from the coffee element required a Starbucks sponsor badge.
As we all expect from a DEF CON badge, there was a crypto challenge and contest. The full write up is available here, with the solution somewhat related to a cube of badges.
A Complete Success
When the badges came back from the fab house, the failure rate for this year’s Queercon badge was 0.7%. That’s an amazing yield for any independent hardware badge, and is honestly one of the most impressive aspects of this year’s Queercon. Failure modes during the con were probably related to spilling a drink on a badge, although there was a rash of failed CPUs. This is probably related to ESD, and during the con rework of failed badges was basically impossible because of drunk soldering in a dimly lit hotel room.
If there’s one failure of this year’s Queercon, it’s simply that it’s becoming too popular. From last year, Queercon saw 200% growth for the main party, which meant not everyone got a badge. That’s unfortunate, but plans are in the works for more inventory next year, providing DEF CON 26 isn’t cancelled, which it is. A shame, really.
The Queercon badge is always a work of art, and this year is no exception. Last year, we took a look at 
