Another long night for the Adafruit Elves, patiently picking apart the latest “Don’t Ask, It’s Not Out Yet”.  I’m often curious how other people in big cities make the most of their typically limited home working space.  Personally I like working at home.  Easy access to Diet Coke, my favorite tea, and a lethargic Shetland warming my feet beneath my desk … nice benefits to have this very cold feeling winter.  I try to make the most of every meter of my limited workspace (Paris is hardly the cheapest place to live), but there are times when it’s just tough to do the tasks at hand with 0.5m² of uncluttered work space at your disposal.  I’ll be moving myself in the coming months and will also get a dedicated office (since eating beside a pick and place sounds cool, but really just isn’t) … but every engineer and serious hobbiest still needs a little workbench somewhere at home for those late nights hacking away at something.  I’m always curious to see other people’s personal workspace, so why not post some links to your own in the comments below!

Thank you all for your previous questions! I hope you have enjoyed the answers and look forward to your future responses.

Currently the list of queued questions is running a bit low, so don’t forget to submit your inquiry via the link below!

For those of you who are new to the scene, I have been teaching high school courses in Energy Systems and Systems Engineering for the past 7 years and use a significant amount of today’s hackerspace technology in my curriculum. If you have any questions about utilizing things like laser engraver/cutters, 3D printers, Arduino, PICAXE, VEX, Vernier, etc. into your curriculum or just general use, I would love to share my opinion!

Submit your question below:
Click here!

A.Khan asks:

“I am trying to use IR sensors to detect where someone is sitting in a room. The IR sensor would be placed on a rotating panel where it will send signals to the microprocessor about where it detects people sitting and the microprocessor can then plot in the 360 circle at which angles it received the input.

For this, what do you suggest is the best way to go? I was thinking more about getting IR body heat sensors premade components (~$6-$10) which give out high or low processed signals when they detect heat and sending it off to an arduino board. But it looks a bit on the expensive side. Is there anyway of creating this setup cheap?

Thanks.”

What a fun question!

I spent the past couple of days coming up with what I think would be viable solution to your problem. To start, Adafruit happens to offer a great little PIR that, as you suggested, responds with a high/low signal in correlation to a IR source crossing its path. Adafruit’s PIR also has a 120 degree viewing angle, which is a bit wide if you are trying to pinpoint a person in a room. Because the device relies on the “path” state to change between the two sides of the sensor and you want to pinpoint a heat source, you will have modify the sensor to limit the viewing angle. You can do this by removing the faceted Fresnel lens and attaching a small tube about 1″ long over the sensor or by covering a percentage of it with some non-transparent tape (this certainly would require some experimentation). Ladyada has a wicked tutorial about PIRs work and how to modify/use it.

The next problem is the fact that you want to view in 360 degrees. I came up with three solutions for this. First, which is the most costly, would be to make your circuitry wireless, relaying the data back to a server. This also poses the problem of powering the device. The second would be to keep the sensor tethered and sweep the device clockwise then counter clockwise. Finally, the third, would be to follow the attached diagram. I had the idea that if you used an 1/8″ stereo “headphone” plug & jack you could simulate a slip-ring (commonly found in wind turbines to transfer electrical energy from the generator in the rotating nacelle). This would allow you to isolate the PIR on a rotating platform and transfer signal/power to the device without interruption. You might want to add a little non-conducting grease to the interface to keep it from wearing out.

In order to make the device rotate, I would recommend using a stepper motor attached to a larger gear, which acts as a yaw bearing for the PIR platform. You can easily control the stepper using an H-bridge (for bipolar) or darlington array (for unipolar) to precisely cover your 360 degrees. Now you get to do the math to determine how many steps per rotation, decoding the PIR, etc.

Click here!

NEW PRODUCT – Clear flip-top storage box. For securely storing small “anythings” (electronics, SMT/SMD components – whatever you need to store) this clear plastic box is a great general purpose flip-top & snap storage box. The snap is sturdy and will not break off. The internal dividers are removable.

• Number of compartments: 12
• Size of compartments: 1.7″ x 2.3″ each
• Size of box: 10.2″L x 4.7″W x 1.6″H

In stock and shipping now!

Have you ever had a pin on a 0.1″ header that you just couldn’t get to reflow properly, especially with lead free solder (which requires a higher temperature to work with)?  If so, it was almost certainly a GND pin connected to a large GND plane.  The problem is that the GND plane dissipates a lot of the heat from the soldering iron.  You can try using a much larger tip (larger tips do a better job of conducting heat that small ones), and/or you may need to jack the heat up quite a bit, but sometimes it just won’t reflow well to form a solid joint.  The solution is easy, but you need to keep the problem in mind when designing the PCB.

What you need to add on any GND pin connected to a GND plane (a large area of copper connected to GND) is to restrict the connection to GND to a single bridge, limiting the other areas with layers 41 (tRestrict) or 42 (bRestrict).  Just select the rectangle tool and draw a small rectangle beside the pad over 3 of the four bridges, and you should have a MUCH easier time soldering those pins on after the fact.  This can also be a good idea with certain large surface-mount parts.

NEW PRODUCT – 5V 10A switching power supply. This is a beefy switching supply, for when you need a lot of power! It can supply 5V DC up to 10 Amps, running from 110V or 220V power (the plug it comes with is for US/Canada/Japan but you can use any plug adapter for your country, or just replace the cable with a standard figure-8 cable)

The output connects to a 2.5mm DC plug but its a ‘springy’ type so you can use it in 2.1mm jacks as well. There’s a green LED indicator lamp as well.

These will be great for people who want to power 5V LED strips or a lot of motors for a CNC project. Using a separate supply like this can be easier than trying to modify an ATX power supply as its smaller, quieter and has a plug on it ready to go!

• 5V up to 10A output
• 110V-220V input
• Comes with 2-prong US/Canada/Japan – for other countries use a basic plug adapter. 112cm (44in) long cable
• 2.5mm output plug, but will also work with 2.1mm. 110cm (42in) long cable
• Body size is 5.5″ x 2.4″ x 1.3″ (14cm x 6 cm x 3.3 cm
• Weight: 0.925 lb / 420g

In stock and shipping now!

Programming prodigy passes away at 16: Hear her philosophy of life -

Arfa Karim Randhawa, the computer programming prodigy who became the world’s youngest Microsoft Certified Professional at 9 years old, has passed away at the age of 16, according to reports out of her native Pakistan this weekend.

…As you’ll hear at the end, Arfa at 10 years old had also settled on her philosophy of life, and committed it to memory. She told me about it after our interview, when she was having her picture taken outside, so I turned my recorder back on and asked her to repeat it for me on tape.

“If you want to do something big in your life, you must remember that shyness is only the mind,” she said. “If you think shy, you act shy. If you think confident you act confident. Therefore never let shyness conquer your mind.”

Sad story, but also filled with hope and inspiration.

NEW PRODUCT – CR2032 Lithium Coin Cell Battery. A perfect match for our sew-able coin cell holder. This non-rechargeable coin cell is CR2032 sized: 20mm diameter, 3.2mm thick. It has a nominal voltage output of 3V (although it starts a little high at 3.2V and slowly drifts down to 2.5V as it is used. The capacity is 220mAh assuming a draw of constant 3nA. For other drain rates the capacity may be reduced, check the datasheet!

In stock and shipping now.

If you’ve ever tried to make a footprint in Eagle with more than one GND, VCC, VDD, NC, etc., pin, you might have noticed that you can’t have two pins with the same names, and you ended up having to name all your GND pins GND1, GND2, GND3, etc.  If you’re mildly OCD like me, this is irksome, but thankfully there’s an easy workaround to this in Eagle.  When defining your schematic symbol and naming each pin, rather than naming pins GND1 take the common name that you want to appear in your schematics and append it with @n.  For example.  GND@1, GND@2, GND@3.  This ensures that each pin has a unique name, but they will all render as GND when placed on your schematic.  Read on to see an image of the the schematic symbol defined for the power pins above (an LPC4350 for the overly curious).

So, please take the following survey and let me know what you think!

——>LINK<——

First of all, Happy New Year to everyone in the OSHW community! 2011 has been an amazing year, and I look forward to everything 2012 has to offer as the community continues to mature and develop.

One of my main resolutions for 2012 was to improve the way that I design, test and document most of the boards I work on, particularly where sensitive analog and high-speed parts are concerned (op-amps, high-resolution ADC inputs, SDRAM, etc.).

This desire to improve in these areas is the result of a number of things, but one of the main reasons is the unique challenges and constraints of OSHW. Unlike the traditional HW development models, OSHW implies working with or for a larger community in a relatively transparent way.  Your audience isn’t just a consumer base purchasing a functional black box, but a wide spectrum of people with varying skills and experience who need to understand not just what a product does, but how the inner workings of it fit together to make it all tick.

OSHW puts a certain obligation on the developer to not just create products that work well, but to detail and document how they work, setting the bar a lot higher in certain areas.  Publishing an open source project can be nerve racking for anyone.  It’s akin to opening your kimono in front of the whole world, but one positive result is the pressure to do things the right way, simply because you know hundreds or thousands of eyeballs will be looking at it.  My own code and design work has actually improved enormously over the years due to this self-inflicted pressure as well as the valuable feedback of others who took the time to (often graciously) point out some things that can be improved in the messy innards of my own code or PCBs.  It’s at times been awkward, and sometimes embarrassing, but and I’m a much better engineer today because of it.

Looking around at the expanding OSHW landscape, I can see a number of tutorials on areas like basic board design, PCB manufacturing, basic coding, etc., but I haven’t seen a lot of articles explaining the hows and whys that go into making products well, or that get into a lot of detail on the messy ‘process’ details that make it possible to get from concept to finished product in a relatively sane and productive manner.  OSHW has done a great job of establishing some ground rules of how things should work and some clear business models are taking shape around OSHW, but there hasn’t (in my opinion) been nearly enough effort in defining how to get there in an intentional, productive way.  There’s a gap between what people want to do, and empowering more people to be able to do it in a productive, meaningful way.

At this point, you’re probably expecting a 10-point list of things that need to be followed to make you a better or more intentional engineer, but as much as I love a good, well-thought out list, this is actually a drum I’d like to beat on throughout the year rather than one big (naively authoritative sounding) article all at once.

I’d like to drag this one out across a number of blog posts, since being a good engineer (or being good at anything you take pride in!) is an endless and highly iterative process where you constantly need to examine (an re-examine) your work, your conception of things, and your methodologies, endlessly asking yourself — and others! — how you could do things better.

I have a number of hard won suggestions I’ve learned the hard way (that I’m happy to pass on to other people to try to shorten their own journey in embedded development), but it all comes down to a single question I often find myself asking to people who express an interest to me in embedded systems or engineering.  Whenever I had to interview a 20-something intern or candidate at a company for a potential position (often their first real engineering job or experience), I’m always sure to ask them the same question: “Do you like learning?  Like, really like learning!?”  Inevitably, I don’t really care what school they went to or how well they can answer that tricky technical trap question.  If I have the impression that they are independent, sufficiently intelligent and genuinely inquisitive, I know that all the technical gaps will naturally fill themselves in.

I always make a point on explaining why I ask that question, though.  The honest answer to it is what will determine whether they will be wonderfully happy or terribly miserable working as an engineer in the embedded world.  Good engineering is a constant learning process, and if you have the right kind of brain that experience will be either the most fulfilling career option you can possibly chose, or the most dreadful.  I’m convinced there isn’t anything in between.  If you like learning, constantly improving and never settling for where you are, you’ll excel.  If you just want the status quo and good enough, you should probably find a different area to work in.

Without getting too far off topic, though, there are a lot of improvements we can all make in the OSHW community whether in design, documentation, development, or  a dozen other Ds.  I have a few articles in the works offering concrete suggestions on some of those things (mostly from looking in the mirror myself), and I hope it will inspire other people in the OSHW community to make more of an effort themselves, and also to offer back some lessons from their own experience.

In any case, I’m looking forward to a great and productive 2012 with Adafruit Industries, as well as with the broader OSHW community!  The whole community has matured a lot this past year, and I’m looking forward to see what everyone else comes up with as that bar is continually being raised higher and higher!

I’m committed to being a better engineering, specifically in a couple areas this year, and I’m happy to try to propose some changes in a concrete way that I hope others can benefit from as well – but what would you like to be better at this year, and what are you going to do to improve on it?  What’s on your engineering reading and ToDo list for 2012?  It’s an important question we should be asking ourselves every day, and not just once a year!

The projects primary mission is to give any educational institution, K-12 and beyond, the opportunity to communicate and manipulate an actual satellite from within the classroom. The satellite contains a voice synthesizer, which when paired with our web interface, will allow for multi-lingual transmission of user submitted voice messages from low earth orbit.

Currently we are preparing to go into our testing phase, which will verify the satellite is fit for flight and we are manifested for launch on NASAs CRS-2 mission in 2012. In addition, we are in the process of making all of our materials available to the public; including PCB designs, code, presentations, and documentation. So that hopefully, this project wont be the last.

Check out the links and I hope you see just how important this community is to inspiring students and teachers alike. And please feel free to ask questions!

So keep those soldering irons warm and Happy New Year!

Adam

P.S. We will be flying Arduino

Links:

http://tj3sat.wikidot.com
http://www.popularmechanics.com/science/space/nasa/nasa-to-launch-the-first-satellites-built-by-high-school-students?click=main_sr
http://www.youtube.com/results?search_query=tj3sat

NEW PRODUCT – Alkaline AAA batteries – 2 pack. Battery power for your portable project! These batteries are good quality at a good price, and work fantastic with any of the kits or projects in the shop that use AAA’s

These batteries are Alkaline (MnO2) chemistry, with a voltage range of 1.6V (fresh) to 0.8V (dead). The mAh capacity depends on discharge usage but at 25mA rate it is 1200mAh (check the datasheet in the download tab for more details)

These work perfectly with the Drawdio kit, Geiger counter kit, Brain machine kit, Ex330 multimeter, and 4xAAA EL wire/tape/panel inverter

In stock and shipping now.

NEW PRODUCT – Panel Mount 2.1mm DC barrel jack. This power jack is designed to easily attach to a panel up to 8mm thick (0.315″ or 5/16″) and fit 2.1mm power plugs snugly and securely. Perfect for adding a power connector to your project enclosure. We like this jack in particular for its long body (so you can use it on thicker wooden panels), sturdy PCB spacer with 3 easy-to-solder eyes and ‘forgiving’ plastic lip that hides the drill hole.

In stock and shipping now!

Mini Thermal Receipt Printer Tutorial! Add a mini printer to any microcontroller project with this very cute thermal printer. Thermal printers are also known as receipt printers, they’re what you get when you go to the ATM or grocery store. Now you can embed a little printer of your own into an enclosure. This printer is ideal for interfacing with a microcontroller, you simply need a 3.3V-5V TTL serial output from your microcontroller to print text, barcodes, bitmap graphics, even a QR code!

Read more!

NEW PRODUCT – Mini Thermal Receipt Printer Starter Pack. Hit the ground running (and printing!) with this starter pack that includes a thermal printer and all the extras and save a few dollars while you’re at it.

Includes:

• A mini thermal receipt printer – with cables and plastic mounting shims
• A roll of 50′ long thermal receipt paper – the perfect amount for the thermal printer
• 5V 2A power supply – an ideal supply for powering the thermal printer (and anything else that can use 5V power
• 2.1mm DC jack adapter – makes it easy to attach the power supply to the printer

We really like this printer because its easy to make Bold, underline, inverted text, variable line spacing, left/center/right justification, barcodes in 11 standard formats with adjustable height, and even custom bitmap graphics.

Of course, we wouldn’t leave you with a datasheet and a “good luck!” – We have a full tutorial and matching Arduino library that demonstrates the following:

• Printing with small, medium and large text
• Bold and underline text
• Inverted text
• Variable
  line
  spacing
• Left, center and right justification
• Barcodes in the following standard formats: UPC A, UPC E, EAN13, EAN8, CODE39, I25, CODEBAR, CODE93, CODE128, CODE11 and MSI – with adjustable barcode height
• Custom monochrome bitmap graphics!
• How to include a QR code

In stock and shipping now!

NEW PRODUCT – Mini Thermal Receipt Printer. Add a mini printer to any microcontroller project with this very cute thermal printer. Thermal printers are also known as receipt printers, they’re what you get when you go to the ATM or grocery store. Now you can embed a little printer of your own into an enclosure. This printer is ideal for interfacing with a microcontroller, you simply need a 3.3V-5V TTL serial output from your microcontroller to print text, barcodes, bitmap graphics, even a QR code!

This package comes with a thermal printer including the print head (it does not require ink, a set of power and data cables, and two plastic shims for panel mounting. Thermal paper not included! The printer uses very common 2.25″ wide thermal paper, available in any office or stationary supply store. It can fit up to 50 ft of paper in the bay at once. You will also need a 5 to 9VDC regulated power supply, that can provide 1.5A or more during the high-current print – our 5V 2A power supply will work very nicely. We also suggest picking up a roll or two of 50′ long thermal paper, and also a 2.1mm jack terminal block adapter which will make it easy to connect the power adapter. We also have a starter pack that includes all the above

We really like this printer because its easy to make Bold, underline, inverted text, variable line spacing, left/center/right justification, barcodes in 11 standard formats with adjustable height, and even custom bitmap graphics.

Of course, we wouldn’t leave you with a datasheet and a “good luck!” – We have a full tutorial and matching Arduino library that demonstrates the following:

• Printing with small, medium and large text
• Bold and underline text
• Inverted text
• Variable
  line
  spacing
• Left, center and right justification
• Barcodes in the following standard formats: UPC A, UPC E, EAN13, EAN8, CODE39, I25, CODEBAR, CODE93, CODE128, CODE11 and MSI – with adjustable barcode height
• Custom monochrome bitmap graphics!
• How to include a QR code

In stock and shipping now!

NEW PRODUCT! – Thermal paper roll – 50′ long, 2.25 wide. A mini roll of thermal paper, this fits very nicely into our mini thermal printer. 2.25″ wide (about 57mm) and 50 feet long (15 meters) Perfect for use with our mini thermal printer and/or mini thermal printer starter pack!

In stock and shipping now!

NEW PRODUCT – 20-pin 0.1 Female header – pack of 5! Female header is like the duct tape of electronics. Its great for connecting things together, soldering to perf-boards, sockets for wires or break-away header, etc. We go through these guys real fast, and thought that given how handy they are, we’d offer them in a pack of five!

Each pack contains five 20-pin long headers, 0.1″ pitch. They’re even gold plated so they wont oxidize! You can cut these down to different sizes fairly easily. First, count how many positions you want as the final piece, then pull out the next pin using a pair of pliers. Finally, cut through the empty spot with diagonal cutters. You can clean off the half-spot using a file or with the diagonal cutters.

In stock and shipping now!

NEW PRODUCT – MCP23008 – i2c 8 input/output port expander. Add another 8 pins to your microcontroller using a MCP23008 port expander. The MCP23008 uses two i2c pins (these can be shared with other i2c devices), and in exchange gives you 8 general purpose pins. You can set each of 8 pins to be input, output, input with a pullup or open drain. There’s even the ability to get an interrupt via an external pin when any of the inputs change so you don’t have to keep polling the chip.

Use this chip from 2.7-5.5V (good for any 3.3V or 5V setup), and you can sink/source up to 20mA from any of the I/O pins so this will work for LEDs and such. Team it up with a high-power MOSFET if you need more juice. DIP package means it will plug into any breadboard or perfboard.

You can set the i2c address by tying the ADDR0-2 pins to power or ground, for up to 8 unique addresses. That means 8 chips can share a single i2c bus – that’s 64 I/O pins!

We used this chip in our SPI/i2c backpack and found it to be very reliable and easy to get up and running. We even have an Arduino library with example code written which will set pin state, read and write from individual pins, and set the pullups.

In stock and shipping now.

I didn’t realize this was only on the French version of google (http://www.google.fr), but today they published the best Google doodle I’ve seen yet in honor of Stanlislaw Lem (Solaris, etc., also turned into a film of the same name Andrei Tarkovsky and again by Steven Soderbergh).  Who else but Google would let you blow up robots with 7-segment displays on their home page (it’s a rhetorical question but if there’s an answer I’d totally love to hear about that too!)?

This potentiometer is a two-in-one, good in a breadboard or with a panel. Its a fairly standard linear taper 10K ohm potentiometer, with a grippy shaft.

Its smooth and easy to turn, but not so loose that it will shift on its own. We like this one because the legs are 0.2″ apart with pin-points, so you can plug it into a breadboard or perfboard. Once you’re done prototyping, you can drill a hole into your project box and mount the potentiometer that way.

In stock and shipping now!

NEW PRODUCT – Little Rubber Bumper Feet – Pack of 4! Keep your electronics from going barefoot, give them little rubber feet! These small sticky bumpers are our favorite accessory for any electronic kit or device.

They are sticky, but not impossible to remove. They’re small enough to fit onto any board, and have just enough height to give clearance to thru-hole soldered components. We love them so much we include them free with every Arduino we sell, but we’ve also had requests to carry them seperately. Comes in a pack of 4 pieces.

In stock and shipping now!

This one kind of caught me off guard when I first heard about it, but NXP recently announced that they would be making their low-power, low-cost 32-bit ARM Cortex M0 chips available in a variety of new hand-solderable packages, including the venerable DIP.  I don’t know if this is a first, but there definately can’t be that many ARM chips out there in DIP … but the more the merrier where hobbiests are concerned.  The LPC1114 runs at speeds up to 50MHz, has 32KB Flash and 8KB SRAM, and is ridiculously cheap in it’s currently available packages … DIP packaging is bound to be more expensive (the dies on these chips are a small fraction of the cost compared to large packaging like that), but I’m curious what price tag they put on them.  NXP has been extremely aggressive with their current M0 pricing, and these chips are clearly aimed at the very cost-sensitive Chinese market (since the cheapest goods are still all hand-assembled), so I’d expect to be the price to be quite attractive.  You can read all the marketting-speak about it here in the original press release.

NEW PRODUCT – Blank SMT Storage Book – 20 pages. This cute hard-covered booklet will make storing your SMT parts a breeze with translucent flip-pages that are designed for keeping taped parts. The book has 20 pages, 19 of them are for 8mm tape (the most common size of tape by far) and 1 page is for 24mm or smaller tape. Each page has multiple ‘slots’ that you can slide your tape into. The slots are about 3.5″ long, and there are 12 per 8mm page and 6 on the 24mm page.

Its easy to slide parts in due to the flexible pages, and you can even write with a sharpie marker onto the slots to help identify the tiny components. These are essentially the ‘blank’ version of our popular 0805/0603 resistor & capacitor books.

In stock and shipping now.

NEW PRODUCT – Thru-hole 5-way Navigation switch. This navigation switch is an intuitive way to add 5 button’s worth of interfacing with a single component. Inside is 5 switches: left, right, up, down and ‘select’ (pressing down), all with a common ground pin. The package isn’t exactly on a 0.1″ grid, but we found that you can push it into a breadboard with a little bending and it snaps in nicely.

In stock and shipping now!

BACK IN STOCK – Lithium Ion Polymer Battery – 3.7v 1300mAh. Lithium ion polymer (also known as ‘lipo’ or ‘lipoly’) batteries are thin, light and powerful. The output ranges from 4.2V when completely charged to 3.7V. This battery has a capacity of 1300mAh for a total of about 4.8 Wh. If you need a larger battery, we also have a 2700mAh model

The batteries come pre-attached with a genuine 2-pin JST-PH connector as shown and include the necessary protection circuitry. Because they have a genuine JST connector, not a knock-off, the cable wont snag or get stuck in a matching JST jack, they click in and out smoothly.

The included protection circuitry keeps the battery voltage from going too high (over-charging) or low (over-use) which means that the battery will cut-out when completely dead at 3.0V. It will also protect against output shorts. However, even with this protection it is very important that you only use a LiIon/LiPoly constant-voltage/constant-current charger to recharge them and at a rate of 500mA or less.

Like most lipos, the batteries we sell do not have thermistors built in. This is why we suggest charging at 1/2C or even less – 500mA max in this case which is how much you can get from a USB port.

In stock and shipping now!

PropGFX shield for the Propeller Platform @ savagecircuits.

Specs:

• TV out (Master, Slave propeller jumpers)
• R/L audio channels (Master, Slave propeller jumpers)
• Wii Classic Controller Interface
• PS2 Keyboard and Mouse Interface
• IR Detector (3v,5v device jumper, Output resistor to support 5v device)

While the Propeller already has video output capabilities, PropGFX improves the quality by adding a second Propeller to the mix.  The code was recently made available under Creative Commons.

From the New York Times:

PAULA PATTERSON was back in her studio the other night, where she has spent nearly every weeknight and too many weekends to admit since January. From her day job as a graphic designer at an executive search firm in Midtown, she takes the subway and the fickle B61 bus to Brooklyn (“I don’t know why they print a schedule,” she said). That leaves her about two hours to build another V-Luxe, the iPad stand she designed as a birthday gift for her boyfriend last summer and soon after decided to market online.

“If there’s one thing I failed to estimate, it was the time this project would take,” said Ms. Patterson, 41, looking exhausted but also relieved, because the last of the V-Luxes were boxed up on her work table, ready to ship.

The recipients were backers Ms. Patterson found last fall, through the Web site Kickstarter. For pledging at least $500 toward her $5,000 financing goal, they are entitled to a finished V-Luxe, which stands about 18 inches high, is made of three species of wood and looks a little like a classic Philco Predicta TV from the 1950s.

In turning to Kickstarter to finance the V-Luxe, Ms. Patterson is among a growing number of designers who are using the site to get their sketch pad ideas into production, through crowd-sourced financing. Scan Kickstarter’s design category, and there are dozens of projects in search of backing, from screen-printed glassware billed as “awesome glasses for awesome people” to a sustainable house intended for use in developing countries.

Read more…

In the lifetime of a college freshman, laptops and all kinds of mobile devices have shrunk from boxy, heavy machines into sleek gadgets. Everything has gotten tiny, including the amount of electricity they need to compute.

In fact, the improvements in the electrical efficiency of computing are nothing short of astonishing. More importantly, they are the necessary precondition for the mobile world of computing you know and love. Let me run through a quick thought experiment so you can see why.

Imagine you’ve got a shiny computer that is identical to a Macbook Air, except that it has the energy efficiency of a machine from 20 years ago. That computer would use so much power that you’d get a mere 2.5 seconds of battery life out of the Air’s 50 watt-hour battery instead of the seven hours that the Air actually gets. That is to say, you’d need 10,000 Air batteries to run our hypothetical machine for seven hours. There’s no way you’d fit a beast like that into a slim mailing envelope.

Fun with a few 9V batteries. (244 of them) @ The Custom Geek…

So I needed a break from working on a project again, and I remembered that I had a bunch of 9V batteries and thought, ‘I wonder if that would be enough voltage to hold an arc?‘. The answer is yes, it would. So I made a little video of melting some alligator clips and crispifying some LED’s, a CD, and a cap. Or at least trying to blow up the cap, that was one tough cookie..

I used 244 9V batteries, that were not new, but not dead. When you do the math, this should be 2,196 Volts, but that is when they are new. I measured (in blocks) 2,000 volts total. Lots of sparky..

NEW PRODUCT – MAX7219CNG LED Matrix/Digit Display Driver. When you need some help driving a lot of LEDs, the MAX7219 is the best friend you could hope for. Many of us know that if you want to control a lot of LEDs, you’ll want to use multiplexing, a technique that lets you control 64 LEDs (say) with only 16 pins (8×8). The annoying thing about ‘plexing is that you need to use 8 power transistors (or a power register/latch, that can supply over 100mA per pin) AND you have to constantly refresh the display to keep the image stable. If you need to get something together quickly, or don’t want to bother with writing all that code, and especially if you want clean wiring, this chip is the one-stop-solution!

The MAX7219 does all the control and refresh work for you in driving either an 8×8 matrix display or 8 x 7-segment displays (usually these also have a dot so its really an 8-segment display) – 64 LEDs total. All you have to do is send it serial commands via the 4-pin SPI interface and it will auto-magically take care of the rest. Wiring is simplified as well, you only need to set the current level for all LEDs with a single resistor instead of 8 and you can also dim the entire display digitally. It’s a thru-hole chip so you can use it in any breadboard, perfboard or other project, although if you’re soldering it in, we suggest using a socket.

In stock and shipping now!

NEW PRODUCT – TPIC6B595 High Power Shift Register. Add a bunch of high-power outputs to a microcontroller system with chainable shift registers. These chips take a serial input (SPI) of 1 byte (8 bits) and then output those digital bits onto 8 pins. You can chain them together so putting three in a row with the serial output of one plugged into the serial input of another to make 3 x 8 = 24 digital outputs. You can chain pretty much as many as you want. This makes it easy to control a lot of outputs like LEDs from only 3 digital microcontroller pins.

This item contains one TPIC6B595 chip! These chips work similarly to the more well known 7HC595s but they are high power drains, able to sink 150mA per pin. They cannot source current so they should be connected to LED cathodes. This makes them ideal for use with LED matrices where you end up sinking 8 or more LEDs at once.

These chips are DIP package so you can easily plug them into any breadboard or perfboard with 0.1″ spacing. They are not the same pinout as ’595s so check the datasheet!

In stock and shipping now.

This would make a good power source for EL panels, 12V stepper motors (for a robot), or analog LED strip such as this 30 RGB LED, 60 LED RGB or warm white). You may want to pick up a DC power plug adapter to connect onto the wires for easy plugging.

Batteries are not included, can be used with any AA-sized Alkaline or Rechargeable batteries.

In stock and shipping now!

The breadboards are mounted onto a metal plate, and comes with 4 colored posts you can use with a bench-top supply. Four bumpers are included, to keep the board from slipping around your desk.

Like nearly all large breadboards, the ‘power rails’ are split in the middle! That means that if you want to plug in a voltage at the top of the board, it wont appear at the bottom. Since this often trips people up, we strongly suggest drawing lines onto the breadboard the moment you get it!

In stock and shipping now.

Pogo Probes! @ The Custom Geek.

Everyone likes new tools right? Well, my eye caught some neat pogo probes posted on the Adafruit Industries Blog a few months back, and was intrigued. I wanted a pair, but I shied away from the short handles. Then, a few days ago, it happened. I was cleaning out one of my toolboxes, and voila! I found a pair of old probes with bent tips, perfect for making into pogo probes. I also had some pogo pins from Adafruit laying around, waiting to be used for something besides having breadboard wars with ‘micro spears’. Anyway, here is how I made them with a few pictures. You will need an old pair of meter probes, pogo pins, a small hand drill, a Dremel with a cut off wheel (a steel hacksaw will also work), a vice, heat shrink, and a few ounces of patience for this project.

Pogo Pins (10 pack). Pogo pins are little spring-loaded contacts, very handy for making jigs, or making momentary (but electrically solid) contacts. We use them by the dozen for making programming and testing jigs but they’re handy also if say you want to JTAG program a board that you cant solder headers to – just shove these thin contacts into the programming cable and press it onto the contacts.

These particular pins are (in our opinion) ideal because they are skinny enough to fit into proto board or perf board – they have a 1.0mm/0.04″ diameter body (the gold part) but the spring contact head is 1.5mm (0.06″) wide. The uncompressed length is 16.5mm/0.65″, compressed is 14mm/0.55″. Check out our tutorial on how we make pogo-pin jigs!”.

In stock and shipping now.

If you’re working in a collaborative environment or if your projects are shared between different teams or companies, having a well defined coding standard can be useful to make sure that your code is easily understandable and maintainable between developers and down the road.

Aside from cosmetic issues like clear and consistent naming conventions (helpful as that is when debugging), a good set of coding standards also includes a lot of hard-won wisdom on what you should or shouldn’t do for reliability reasons as well.

While certain development platforms like C# (.Net) tend to have a single widely accepted ‘coding standard’ (the “IDesign C# Coding Standard” probably being the best and most widely adopted for that platform), things are a bit less homogonous for C (more broadly) or embedded C (specifically), and a few different ‘styles’ exist (K&R C, etc.).

A lot of this comes down to personal preference, but the following resources may be useful if you’re trying to improve your own coding, particularly for embedded systems where you have some unique safety and practical concerns.

Software Development with C – Coding Guidelines
A summary of current coding standards from Alexander Neundorf at the Technische Universität Kaiserslautern, this presentations has a good summary of C Coding Standards if you’d like a more in-depth description of why having a coding standard is important and what some of your options are.

MISRA C:2004 (MISRA C2)

MISRA is the “Motor Industry Software Reliability Association”, and amongst many other publications they have published, their “Guidelines for the Use of the C Language in Critical Systems” has been widely adopted both inside and outside of the automotive industry. As a ‘standard’, it’s quite restrictive, but this goes with the nature of safety-critical systems such as automotive, medical devices, etc. This particular standard sets the bar pretty high, but it also gives you a high confidence in the portability of your code and can help avoid a wide variety of common pitfalls that can be difficult to debug in the field. A number of automatic tools existing for checking code compliance again MISRA C and several high end compilers integrate support for checking MISRA C compliance, but they are all commercial and tend to be prohibitively expensive for hobbiest use. A PDF version of the MISRA C standard can be purchased for 10 British Pounds from MISRA Website, and is worth the investment if you want to develop safety critical or highly reliable systems.

JOINT STRIKE FIGHTER AIR VEHICLE C++ CODING STANDARDS - (Alternatively: PDF File)

While this standard from Lockheed Martin Corporation is aimed at C++, there is a great deal of information that can be adopted for C development as well, and the document can be freely downloaded from numerous places on the web. They draw extensively on the MISRA standards mentionned above, but also offer a lot of general explanations and comments that can be a good reminder for both experience and beginning embedded developpers.

JPL Institutional Coding Standard for the C Programming Language

Published by the Jet Propulsion Laboratory at the California Institute of Technology, this C coding standard is also freely available on the web, and is more concise than the JSF Standard above, though it is also much higher-level and doesn’t go into nearly the same detail. It can be a good high-level overview of what key pitfalls to avoid and is worth reading through and making some notes in the margins when developping your own coding style. Some of the higher level recommendations to ensure code maintanability are:

• Rule 2 (routine checking): All code shall always be compiled with all compiler warnings enabled at the highest warning level available, with no errors or warnings resulting. All code shall further be verified with a JPL approved state-of-the-art static source code analyzer, with no errors or warnings resulting. [MISRA-C:2004 Rule 21.1]
• Rule 25: Functions should be no longer than 60 lines of text and define no more than 6 parameters. [Power of Ten Rule 4]

BY POPULAR REQUEST! NEW PRODUCT – Extra-long break-away 0.1 18-pin strip male header (5 pieces). Breakaway header is like the duct tape of electronics, and this header is one better with extra long pins on both sides. This makes it great for connecting things together that have two sockets – especially solderless breadboards. We also use these with our female-female socket jumpers to create female-male and male-male jumpers! Each pack contains 5 x 18-pin long headers, 0.1″ pitch, that can be stacked next to each other on a 0.1″ grid and broken apart easily with pliers or diagonal cutters. They’re even gold plated so they wont oxidize!

In stock and shipping now.

While books of phone schematics are common place in Shenzhen (and probably throughout China),an interesting website came up in my search results for something completely unrelated.  Ever wonder how mobiles phones are designed to pack so much functionality into increasingly smaller packages?  Have a look at cellphonediagram.com and you should find a lot of interesting material to learn from.

This is the same sensor used in the breakout board we just put in the store. It can determine barometric pressure with high precision, good for determining altitude and weather patterns! If you want to integrate this into a future project, you’ll want to pick up some raw sensors. They’re fairly easy to solder and our Arduino library has all the math worked out for you. You can even use the Adafruit eagle library which has this sensor as a ready-to-go package!

READ MORE…

NEW PRODUCT – Pogo Pins (10 pack). Pogo pins are little spring-loaded contacts, very handy for making jigs, or making momentary (but electrically solid) contacts. We use them by the dozen for making programming and testing jigs but they’re handy also if say you want to JTAG program a board that you cant solder headers to – just shove these thin contacts into the programming cable and press it onto the contacts.

These particular pins are (in our opinion) ideal because they are skinny enough to fit into proto board or perf board – they have a 1.0mm/0.04″ diameter body (the gold part) but the spring contact head is 1.5mm (0.06″) wide. The uncompressed length is 16.5mm/0.65″, compressed is 14mm/0.55″. Check out our tutorial on how we make pogo-pin jigs!”.

In stock and shipping now.

NEW PRODUCT – Break-away 0.1 36-pin strip male header (10 pieces). Breakaway header is like the duct tape of electronics. Its great for connecting things together, soldering to perf-boards, fits into any breakout or breadboard, etc. We go through these guys real fast, and thought that given how handy they are, we’d offer them in a pack of ten!

Each pack contains 10 36-pin long headers, 0.1″ pitch, that can be stacked next to each other on a 0.1″ grid and broken apart easily with pliers or diagonal cutters. They’re even gold plated so they wont oxidize!

In stock and shipping now…

UPDATED PRODUCT – USB LiIon/LiPoly charger – v1.2. This is a Lithium Ion and Lithium Polymer battery charger based on the MCP73833. It uses a USB mini-B for connection to any computer or ‘USB wall adapter’. Charging is performed in three stages: first a preconditioning charge, then a constant-current fast charge and finally a constant-voltage trickle charge to keep the battery topped-up. The fast-charge current is 500mA by default, but is easily adjustable from 100mA up to 1000mA by soldering a through-hole resistor on-board.

This board is great for DIY projects because it has 3 indicator LEDs – one for power, one for charging status and a third that indicates when charging is complete. Keep the battery connected to the charger and pass power through the additional JST connector using the included cable!

• Comes assembled and tested with a free bonus JST cable!
• 5V input via mini-B USB connector
• For charging single Lithium Ion/Lithium Polymer 3.7/4.2v batteries (not for older 3.6/4.1v cells)
• 500mA charge current, adjustable from 100mA to 1000mA by soldering in a resistor
• Separate JST connectors for battery and load system so batteries don’t have to be removed for charging
• Chip supports a 10K NTC thermistor which we have stuffed as a plain 10K. For people who require temperature monitors (using high charge rates), remove the 10K and solder in the thermistor in its place
• 0.1″ (2.54mm) breakouts for the battery, DC, and status LEDs
• Free 2-pin JST cable included!
• Batteries and USB cable not included.

In stock and shipping now!

If you’re interested in making the plunge from Arduino (etc.) to directly working with an MCU, you’ll inevitably have to learn some basic C.  There are a number of books that can teach you the basics, but if you’re looking for a refresher on one specific topic or keyword, “The C Book” is a great (and surprisingly thorough) online resource.  Have another suggestion for people interested in getting start in C?  Feel free to leave a suggestion in the comments!

NEW PRODUCT – 28-pin ZIF socket. A ZIF (Zero Insertion Force Socket) allows you to insert and remove chips easily from an existing circuits. These are often used for chip programmers or when you need to test a chip without damaging it. Move the lever up and chips drop right in. Move the lever down to ‘latch’ the chip in place.

This socket is designed for DIP chips of up to 28 pins and 0.3″ wide. What’s nice about it is it can snap into an existing circuit board or socket that is designed for the chip so you may not have to redesign the board! For example, we snapped it into an Arduino socket, which would allow you to change chips out (if you wanted to put a shield on top, you’ll need to fit a set of stacking headers on).

In stock and shipping now.

NEW PRODUCT – 40-pin ZIF socket. A ZIF (Zero Insertion Force Socket) allows you to insert and remove chips easily from an existing circuits. These are often used for chip programmers or when you need to test a chip without damaging it. Move the lever up and chips drop right in. Move the lever down to ‘latch’ the chip in place.

This socket is designed for DIP chips of up to 40 pins and up to 0.6″ wide. So really, its good for any size chip you’ll find. What’s nice about it is it can snap into an existing circuit board or socket that is designed for a 40-pin 0.6″ chip so you may not have to redesign the board! This socket is gold plated so it will last a long time.

In stock and shipping now.

PART FINDER! Rotary Encoder – Rotary encoders are useful as rotation sensors or selectors and look similar to potentiometers. However they are not like potentiometers at all, so it’s important to realize the difference! These rotary encoders rotate all the way around continuously, and are divided up into 24 ‘segments’. Each segment has a click-y feeling to it, and each movement clockwise or counter-clockwise causes the two switches to open and close. There is no way to know what the current ‘position’ is – instead you would use a microcontroller to count how many ‘clicks’ left or right it has been turned. If you need to detect rotational ‘position’ a potentiometer would be a better choice.

READ MORE!

NEW PRODUCT – Rotary Encoder + Extras – This rotary encoder is the best of the best, its a high quality 24-pulse encoder, with detents and a nice feel. It is panel mountable for placement in a box, or you can plug it into a breadboard (just cut/bend the two mechanical side tabs.) We also include a nice soft-touch knob with an arrow in it, fits perfectly and looks great. This encoder also has a push-button built into it so you can press onto the knob to close a separate switch. One side has a 3 pin connector (ground and two coding pins) and the other side has two pins for a normally-open switch.

Rotary encoders are useful as rotation sensors or selectors and look similar to potentiometers. However they are not like potentiometers at all, so it’s important to realize the difference! These rotary encoders rotate all the way around continuously, and are divided up into 24 ‘segments’. Each segment has a click-y feeling to it, and each movement clockwise or counter-clockwise causes the two switches to open and close. There is no way to know what the current ‘position’ is – instead you would use a microcontroller to count how many ‘clicks’ left or right it has been turned. If you need to detect rotational ‘position’ a potentiometer would be a better choice.

In stock and shipping now.

Perfect for adding a power connector to your project. We went for the more expensive “thin pin” type which snap into breadboards or perfboards. They will work where “thick pin” types go also, just need a little more solder to fill up the larger pads.