An October 6th Press Release from the FAA states that SkyPan International, a Chicago based aerial photography company conducted 65 unauthorized operations over a 2+ year period resulting in a $1.9M penalty. This is by far the most severe penalty the FAA has proposed, the previous leader being $18,700 against Xizmo Media which was issued in September.
SkyPan International isn’t your suburban neighbor’s spoiled brat kid who flies his new octocopter through the neighborhood with his HD camera running in hopes to catch…well, you get the idea. SkyPan has been in the aerial photography game for 27 years and was awarded a Section 333 Exemption from the blanket ban of commercial UAS (unmanned aircraft systems) operation from the FAA in 2015. They also proactively contacted the FAA in 2005, 2008, and 2010 to discuss and suggest technical regulatory parameters. The seemingly civil history between the two entities leaves things in a confusing state, which seems to be par for the course when it comes to UAS.
Everyone has their favorite process for PCB fabrication, as long as you’re a happy hacker I don’t think it really matters. But in this post I thought it might be interesting to describe my personal process, and some of the options available.
Making your own at home
The Dirty Electronics Skull Etching Synth a great looking maskless board.
Etching is the classic PCB fabrication option for the home hacker. It’s been many, many years since I etched a PCBs but it can produce interesting results. Some people don’t like it, and I’d personally tend to avoid it as a messy and finicky process. But, if you only need 1 or 2 layer boards with large features (through-hole components are best of course) it can be a viable option. In some cases, I think etched boards look awesome and are a great fit. One example is the skull etching shown to the right. The oxidation and discoloration of the boards adds to the design aesthetic in this case.
A simple design milled on an Accurate CNC
For those with a bigger budget a professional milling machine might be a viable choice. I’ve used an Accurate CNC in the past (LPKF and others make mills too), but this is an expensive option (no online pricing, but if $10,000 USD is a lot for you don’t bother). The accurate mill is pretty awesome, it can be fitted with a vacuum bed, automatic tool changer and vision system for alignment. The mill can produce high quality two layer boards with all the holes and vias drilled out. The final step of filling the vias is however manual, but compared to etched boards the results are pretty professional (the mill itself uses milled PCBs!). They claim a 0.1mm (4 mil) track size, I’ve never tried tracks this small but surface mount components were not a problem.
While a fun toy, it’s worth considering if you really need a PCB mill. The only case where they’re really valuable is if you want to be able to iterate over a design with less than a days turn around. This can be useful in RF or low noise designs where you might want to experiment with different layouts, but for other projects the price of a good mill can pay for quick turn around (1 or 2 days from order submission to delivery) on a lot of boards.
Commercial Fabrication
Years ago commercial fabrication used to be a very expensive and finicky process. For the most part you’d need to order a full panel putting the service outside of most hobbyists reach. Generating gerbers and drill files to the fabs specification could also be a process fraught with complication.
These days services that aggregate designs onto a single panel and break them out for distribution are common. For my work I mostly stick with OSHPark and SeeedStudio whose services complement each other well. I’ve also used Itead and found them compatible with Seeed (with the added benefit that they supply free boards for open projects).
Using OSHPark gives me the warm fuzzies. A child of the hacker community, born out of DorkbotPDX, all OSHPark’s boards are fabbed in the US (check out the great amphour interview for more details). Their services are limited to either 2 or 4 layer boards (always in purple, and always coated with gold (ENIG)), in 6×6 (6 mil traces with 6 mil spacing) or 5×5. I rarely attempt BGA boards so the 2 layer service works out great for me. OSHPark’s minimum order is 3 boards, which is perfect for prototyping. The gold plating also provides a nice finish, which both protects the board from oxidation and provides a nice surface to solder to. The main reason I use OSHPark however is that they’re cheap for small boards and have a relatively fast turn around (I recently purchased 3 tiny 20x15mm boards for $2.40 including shipping which was unbeatable). From OSHPark in the US to the UK my boards take about 2 weeks to arrive. They’ve also automatically upgrade boards to their super-swift service for free when there’s spare capacity. Their service is pretty slick, and provides a rendering of the gerbers prior to ordering as a final check which comes in very handy.
Seeed on the other hand are much cheaper for larger size boards and volume orders. They also provide more color and finishing options. The cheapest option at Seeed is green PCBs with HASL finish (hot air solder leveling). From Seeed, my boards usually take about a month to arrive (there are a few delivery options, but in my experience this is about as fast as it gets and faster shipping services often make using Seeed less attractive).
The image to the right shows a couple of very simple boards I had manufactured at both OSHPark and Seeed. I’ve never had a fabrication issues with boards from either service (though I prefer the ENIG finish).
Partly due to the limitations imposed by using commercial fabs I pipeline my projects. I send projects out to fab early in the design process and then switch to another design. When the board comes back I bring it up, bodge as required, and iterate over the layout. This works well with a two-week turn around, so I mostly use OSHPark while prototyping.
My boards also tend to be quite small (Arduino shield size or a little bigger). With small boards like this OSHPark is usually on-par or cheaper than ordering from Seeed (whose minimum quantity is 10 boards). With boards of about 100x100mm or larger I consider Seeed as they become significantly cheaper.
As a hobbyist I also rarely need huge numbers of boards, but for workshops when I need 10 or 20 boards I order from Seeed based on the final iteration of my prototypes. This is not only much cheaper than OSHPark, but I can get boards in a variety of colors to make workshops more interesting too.
This post has described some of the available options and my personal process. I hope it’s been interesting, but I’d love to hear about your favorite fabrication techniques, services and experiences both good and bad too. Please comment below!
[mosaicmerc] over on hackaday.io has upgraded his Rigol DS2072A oscilloscope to a DS2302A, turning an $800 oscilloscope into one that sells for $2500, with all the bandwidth, storage depth, and options of the more expensive model.
Rigol o-scopes have a long and storied history of unlocking, hacking, and upgrading. The original hack that put Rigol on the map was the DS1052E upgrade that turned a 50MHz scope into a 100MHz scope. The latest low-end Rigol scope, the 1054Z can be unlocked in software to become an 1104Z with 100MHz of bandwidth, SPI, I2C, and RS232 decoders, twice the storage depth, and more triggers. It appears Rigol’s engineers are designing their products to capitalize on the hacker’s proclivity to buy their tools to get the ‘free’ upgrade. This, of course, sounds just slightly insane, but no one seems to mind.
The process of upgrading the Rigol DS2072A scope is documented over on the EEVBlog, and requires only a USB cable and a computer with the Labview Runtime Engine installed. It’s literally as simple as pressing a few buttons; a far cry from the previous keygen method that was also engineered over on the EEVBlog.
On February 25, 1991, during the eve of the of an Iraqi invasion of Saudi Arabia, a Scud missile fired from Iraqi positions hit a US Army barracks in Dhahran, Saudi Arabia. A defense was available – Patriot missiles had intercepted Iraqi Scuds earlier in the year, but not on this day.
The computer controlling the Patriot missile in Dhahran had been operating for over 100 hours when it was launched. The internal clock of this computer was multiplied by 1/10th, and then shoved into a 24-bit register. The binary representation of 1/10th is non-terminating, and after chopping this down to 24 bits, a small error was introduced. This error increased slightly every second, and after 100 hours, the system clock of the Patriot missile system was 0.34 seconds off.
A Scud missile travels at about 1,600 meters per second. In one third of a second, it travels half a kilometer, and well outside the “range gate” that the Patriot tracked. On February 25, 1991, a Patriot missile would fail to intercept a Scud launched at a US Army barracks, killing 28 and wounding 100 others. It was the first time a floating point error had killed a person, and it certainly won’t be the last.
Maker Faire Rome is over, and that means it’s time for the Arduino media blitz. Arduino has already had a big announcement this week with the introduction of the Arduino / Genuino 101 board powered by the Intel Curie module. Team .cc hasn’t forgotten all their Atmel-powered boards though. The latest news is that Arduinos will be manufactured in Germany by Watterott Electronics (.de, Google Translate).
Right now, Arduino.cc boards are manufactured in China by Seeed, and in the US by Adafruit and Sparkfun. Watterott Electronics is one of the premier hobby electronics distributors in Germany.
Boards made by Watterott will carry the Genuino mark; Arduino.cc seems to anticipate a loss in the Arduino vs. Arduino trademark dispute outside the US. All boards produced under license from Arduino.cc sold outside the US will carry the Genuino trademark, whereas boards produced for the US market will carry the Arduino trademark. Interestingly, this Arduino vs. Arduino split began with a former manufacturer, with a maelstrom of pettiness stemming from that trademark dispute. In any case, the licensing for boards manufactured by Watterott is most assuredly worked out by now. The new manufacturing partner guarantees a greater supply of Arduinos for all.
Today when you want to upgrade your computer you slap in a card, back in the early 80’s things were not always as simple. When [Carsten] was digging around the house he found his old, and heavily modified Rockwell AIM 65 single board computer, flipped the switch and the primitive 6502 machine popped to life.
Added to the computer was a pile of wires and PCB’s in order to expand the RAM, the I/O to form a “crate bus” and of course tons of LED blinkenlights! On that bus a few cards were installed, including a decoder board to handle all the slots, a monitor controller, a massive GPIO card, and even a universal EEPROM programmer.
If that was not enough there was even a OS upgrade from the standard issue BASIC, to a dual-boot BASIC and FORTH. Though again unlike today where upgrading your OS requires a button click and a reboot, making all these upgrades are planned out on paper, which were scanned for any retro computer buff to pour through.
[Carsten] posted a video of this computer loading the CRT initilization program from a cassette. You can watch, but shouldn’t listen to that video here.
The summer may have come to a close here in the USA, but any time of the year is a good time for grilling. In the colder weather, it’s a drag to have to stay near the hot grill to keep an eye on your burgers and franks. [Eric Ely] thought it would be smarter to have a meat thermometer that sent his phone the current reading via Bluetooth.
Instead of starting from scratch, [Eric] took an off the shelf electronic thermometer and removed its temperature probe (which was a thermistor). The hardware used an off the shelf Bluetooth board with a companion battery board and prototype board. If you can’t bear to cut up a good thermometer, you can get replacement probes that ought to work just as well.
In addition to the boards and the scavenged thermistor, [Eric] used a couple of resistors. One resistor is in parallel with the thermistor to improve the linearity of the device’s response curve. The second resistor forms a voltage divider that the Bluetooth board reads.
The software (using Node.js and C) is available on Github. The C program reads the temperature and pushes it out using JSON. Node.js provides a server that [Eric] can hit with his phone’s Web browser.
Sure, you can buy wireless thermometers, but what self-respecting hacker wants to carry around a store-bought box just to display meat temperature? Viewing it on your phone has much more street cred. Of course, a real hacker isn’t going to cook on a conventional grill, either.
