Royal Institution Christmas Lectures

via Raspberry Pi

As you may have heard if you follow us on Twitter, Facebook or G+, we are sponsoring this year’s Royal Institution Christmas Lectures. The lectures are part of British educational history: Michael Faraday started them in 1825 to introduce science to ordinary people – especially young people – and they’ve been running ever since, with only one break in 1939-42 during World War II.

Professor Danielle George, presenter of this year's lectures. Photo credit: Paul Wilkinson

Professor Danielle George, presenter of this year’s lectures. Photo credit: Paul Wilkinson

We’re incredibly proud to be associated with the lectures. They’re a real educational jewel, and they provide some of the best television in the UK over the Christmas period. British readers can watch this year’s lectures on BBC4 on December 29, 30 and 31 – the theme (which, serendipitously, has a lot of relevance for Raspberry Pi users) is Sparks will fly: How to hack your home. International viewers will be able to watch later on on the Royal Institution’s website.

Here’s a teaser the Royal Institution released on YouTube yesterday.

If you’d like to read more about this year’s lectures, there’s a long interview with Professor Danielle George in the Guardian, where she explains why hacking is such a crucial skill for children. We hope you’ll be watching the lectures along with us!

OSHWA is having a Membership Drive!

via Open Source Hardware Association

We are launching a Membership Campaign to double our members of like-minded individuals and companies between now and January 15, 2015. Help us reach our goal by spreading the word: We will keep you all updated on our membership drive as things progress. If you have innovative ideas on how we can attract more members, please get in touch with Aileen at We welcome your ideas.

Tweet: OSHWA is building a future for open source hardware - become a member! #joinoshwa Help us spread the word about OSHWA’s Membership Drive with a Tweet!

Handy Arduino makes it on french television

via Arduino Blog


Last saturday, Arte tvl aired a short documentary in french language about Arduino. The video was created by FUTURE magazine and featuring Massimo Banzi, David Cuartielles and Arduino users: children and young electronics enthusiasts:

Tinkering in a garage on a drone, playing with a set of lights with LEDs or even build a robotic arm worthy of a science fiction movie … Today, even when one is a novice in electronics all this is possible through Arduino, a real flexible technology.

They also created two nice short info-animations to explain what is Arduino and the idea of open source:

Designing for Graceful Failure

via SparkFun Electronics Blog Posts

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That’s a pair of Fetco CBS2131XTS-3Ls - they are our new coffee machines. They are massive and shiny - and a huge step up from our old Newco Machine. Why are we talking about coffee machines? Well, take a look at the screen that popped up on the one on the left a few weeks back…

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“Internal error in file: qa_fifo in line: 81. For Service call: +1 (800) 338-2699”

One otherwise normal morning, the machine came up with this error - which seems not great. What does this mean for my morning coffee? DOES THIS MEAN NO COFFEE?!

After filling our cups from the second machine, we calmed down and did some research. Apparently we weren’t the first people to encounter this error message. The bit of code in question can be found here.

Turns out, this was a problem that popped up during the initialization process. The fix was - as it is in so very many cases - turning the machine off and on. As an aside, don’t you wish life was like that? Crappy day? Turn it off and on and start over! But I digress…

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This, like our dear coffee maker, is not a graceful failure. (Image courtesy of

The purpose behind this post is to start the conversation about failure – and how we should design technology to fail gracefully. Because, quite frankly, you need to be prepared for your design to fail. I know, I know — your code is perfect, your hardware choices impeccable and you are thorough in your assembly and review. But it happens to even the most well-designed and well-built projects.

This particular coffee machine failure is not what we would call graceful. The machine went wonky and it popped up with a fairly unhelpful error message - and then it didn’t work at all. No coffee brewing here, folks. If I want a cup of joe, I should call that number, I guess? Do they deliver it by drone?

Before we dive any further, an open letter to Fetco:

Dear Fetco,

Seriously? Like...seriously? 


This isn’t just a normal coffee maker. It has a init file, for heaven’s sake. It’s also a very expensive coffee maker. We are sort of particular about our coffee and we drink a lot of the stuff. We think Fetco could have done a lot better. For example, if an error like this one kicked the brewer into a “You don’t need the touchscreen - you just need caffeine” mode. If this is the promised land of the “Internet of Things, I’m not sure I want to go there.

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The “Red Ring of Death” (image courtesy of Wikipedia)

Unfortunately, clumsy failures are all over the place. For example, the “Red Ring of Death” failure on the original Xbox 360 game console. While Microsoft never really admitted to what was causing the issue, third-party tests basically narrowed it down to an overheating problem caused by the graphics chip. The unit became so hot that it de-soldered itself from the PCB. Whether it was really a problem with the chip or with the Xbox’s cooling system is debatable, but when it failed, it failed hard. There were all kinds of crazy fixes - including wrapping your Xbox in towels so it got so hot it re-soldered itself - but the issue effectively bricked your system. Maybe when the system started to overheat, it could’ve shut down - thus preserving you’re ability to “live to fight another day?”

Designing something to fail gracefully - sometimes called “graceful degradation” or simply “fault tolerance” - means that, as the design fails, its core functionality remains useable or the error at least creates as little collateral damage as possible. Wouldn’t it be nice if when the hard drive in your PC went kaput, it didn’t take all your data with it?

On the other hand, an example of something that fails gracefully relates to the “Transmission Control Protocol,” which allows reliable two-way communication in a packet-switched network, even when the communication links are jammed up.

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Designing something to fail gracefully is often a case of what I call “design introspection.” Despite your prodigious skills as a coder of code and hacker of hacks, if something were to go wrong, what would it be? And let’s just put it this way - something is going to go wrong. Something will break. When it does, how do you want it to look and sound? What should it do? How should you “design for failure?”

It can be hard to look at a project objectively – especially when you’ve invested a whole bunch of time, effort and money in the build. But if you can identify the most likely culprits for a would-be failure, you can add redundancies, self-stabilization procedures (ooh, what’s that?) or failsafes that would make a potential failure – even a big/catastrophic one – not as bad as it otherwise would or could be.

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What could possibly go wrong?

It’s also helpful (and, frankly, imperative) to identify your design’s “core function.” Which is exactly what it sounds like – at its heart, what is this thing supposed to do? In the case of the coffee maker, that’s pretty easy - it’s supposed to brew coffee. Protect the core function! If your fancy device has a bunch of extra features (say, a touchscreen), that aren’t necessary to do its job (say, brew coffee - AHEM, Fetco!) then if these extraneous things stop working for whatever reason, try to preserve the core function.

In the case of the coffee brewer gone rogue, what would this have looked like? The error itself was pretty minor – pretty much just a hiccup during boot. No one stuffed an old sock in the grinder or punched a hole through the screen in a caffeine-deficient rage. But it rendered the coffee pot unusable. In this specific case, it would’ve been ideal if there was a manual override or safe-setting. Fetco failed to protect its products core function - and that stinks.

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No LCD screen – but also pretty darn reliable. Decisions, decisions… (Image courtesy of

With all of this in mind, we’re wondering - what hardware failures have you encountered that were decidedly ungraceful? What processes do you use to design your projects to fail with all the elegance of a ballerina?

We’d love to hear in the comments below! Now go forth - and fail well!

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Controlling Telescopes with Raspberry Pi and Mathematica

via Raspberry Pi

Eben: Here’s a guest post from Tom Sherlock, describing how he’s been able to control a telescope using a Raspberry Pi, Mathematica and the Wolfram Language.

As an amateur astronomer, I’m always interested in ways to use Mathematica in my hobby. In earlier blog posts, I’ve written about how Mathematica can be used to process and improve images taken of planets and nebulae. However, I’d like to be able to control my astronomical hardware directly with the Wolfram Language.

In particular, I’ve been curious about using the Wolfram Language as a way to drive my telescope mount, for the purpose of automating an observing session. There is precedent for this because some amateurs use their computerized telescopes to hunt down transient phenomena like supernovas. Software already exists for performing many of the tasks that astronomers engage in—locating objects, managing data, and performing image processing. However, it would be quite cool to automate all the different tasks associated with an observing session from one notebook.

Mathematica is highly useful because it can perform many of these operations in a unified manner. For example, Mathematica incorporates a vast amount of useful astronomical data, including the celestial coordinates of hundreds of thousands of stars, nebula, galaxies, asteroids, and planets. In addition to this, Mathematica‘s image processing and data handling functionality are extremely useful when processing astronomical data.

Previously I’ve done some work interfacing with telescope mounts using an existing library of functions called ASCOM. Although ASCOM is powerful and can drive many devices associated with astronomy, like domes and filter wheels, it is limited because it only works on PCs and needs to be pre-installed on your computer. I wanted to be able to drive my telescope directly from Mathematica running on any platform, and without any special set up.

Telescope Serial Communication Protocols

I did some research and determined that many telescope mounts obey one of two serial protocols for their control: the Meade LX200 protocol and the Celestron NexStar protocol.

The LX200 protocol is used by Meade telescopes like the LX200 series as well as the ETX series. The LX200 protocol is also used by many non-Meade telescope mounts, like those produced by Losmandy and Astro-Physics.

The NexStar protocol is used by Celestron telescopes and mounts as well as those manufactured by its parent company, Synta, including the Orion Atlas/Sirius family of computerized mounts.

The full details of these protocols can be found in the Meade Telescope Serial Command Protocol PDF and the NexStar Communication Protocol PDF.

A notable exception is the Paramount series of telescope mounts from Software Bisque, which use the RTS2 (Remote Telescope System) protocol for remote control of robotic observatories. The RTS2 standard describes communication across a TCP/IP link and isn’t serial-port based. Support for RTS2 will have to be a future project.

Since Mathematica 10 has added direct serial-port support, it’s possible to implement these protocols directly in top-level Wolfram Language code and have the same code drive different mounts from Mathematica running on different platforms, including Linux, Mac, Windows, and Raspberry Pi.

Example: Slewing the Scope

Here’s an example of opening a connection to a telescope mount obeying the LX200 protocol, setting the target and then slewing to that target.

Open the serial port (“/dev/ttyUSB0″) connected to the telescope:

theScope = DeviceOpen["Serial", 
{"/dev/ttyUSB0", "BaudRate" -> 9600, 
"DataBits" -> 8, "Parity" -> None, 
"StopBits" -> 1}];

First we need a simple utility for issuing a command, waiting for a given amount of time (usually a few seconds), and then reading off the single-character response.

ScopeIssueCommand1[theScope_, cmd_String]:=
   DeviceWrite[theScope, cmd]; 

These are functions for setting the target right ascension and declination in the LX200 protocol. Here, the right ascension (RA) is specified by a string in the form of HH:MM:SS, and the declination (Dec) by a string in the form of DD:MM:SS.

ScopeSetTargetRightAscension[theScope_,str_String] := ScopeIssueCommand1[theScope,":Sr"<>str<>"#"];

ScopeSetTargetDeclination[theScope_,str_String] := ScopeIssueCommand1[theScope,":Sd"<>str<>"#"];

Now that we have the basics out of the way, in order to slew to a target at coordinates specified by RA and Dec strings, setting the target and then issuing the slew command are combined.

   theScope_, ra_String, dec_String]:=
   ScopeSetTargetDeclination[theScope, dec];

We can also pass in real values as the coordinates, and then convert them to correctly formatted strings for the above function.

   theScope_, ra_Real, dec_Real]:=
   ScopeSlewToRADecPrecise[theScope, rastr, decstr]

Now we can point the scope to the great globular cluster in Hercules:


Slew the scope to the Ring Nebula:


And slew the scope to Saturn:


When the observing session is complete, we can close down the serial connection to the scope.


Please be aware that before trying this on your own scope, you should have limits set up with the mount so that the scope doesn’t accidentally crash into things when slewing around. And of course, no astronomical telescope should be operated during the daytime without a proper solar filter in place.

The previous example works with Mathematica 10 on all supported platforms. The only thing that needs to change is the name of the serial port. For example, on a Windows machine, the port may be called “COM8″ or such.

Telescope Control with Raspberry Pi

One interesting platform for telescope control is the Raspberry Pi. This is an inexpensive ($25–$35), low-power-consumption, credit-card-sized computer that runs Linux and is tailor-made for all manner of hackery. Best of all, it comes with a free copy of Mathematica included with the operating system.


Since the Pi is just a Linux box, the Wolfram Language code for serial-port telescope control works on that too. In fact, since the Pi can easily be wirelessly networked, it is possible to connect to it from inside my house, thus solving the number one problem faced by amateur astronomers, namely, how to keep warm when it’s cold outside.

The Pi doesn’t have any direct RS-232 ports in hardware, but an inexpensive USB- to-serial adapter provides a plug-n-play port at /dev/ttyUSB0. In this picture, you can see the small wireless network adapter in the USB socket next to the much larger, blue, usb-to-serial adapter.


Astrophotography with the Pi

Once I had the Pi controlling the telescope, I wondered if I could use it to take pictures through the scope as well. The Raspberry Pi has an inexpensive camera available for $25, which can take reasonably high-resolution images with a wide variety of exposures.


This isn’t as good as a dedicated astronomical camera, because it lacks the active cooling needed to take low-noise images of deep sky objects, but it would be appropriate for capturing images of bright objects like planets, the Moon, or (with proper filtering) the Sun.

It was fairly easy to find the mechanical dimensions of the camera board on the internet, design a telescope adapter…


…and then build the adapter using my lathe and a few pennies worth of acetal resin (Dupont Delrin®) I had in my scrap box. The normal lens on the Pi camera was unscrewed and removed to expose the CCD chip directly because the telescope itself forms the image.


Note that this is a pretty fancy adaptor, and one nearly as good could have been made out of 1 1/4 plumbing parts or an old film canister; this is a place where many people have exercised considerable ingenuity. I bolted the adaptor to the side of the Pi case using some 2-56 screws and insulating stand-offs cut from old spray bottle tubing.


This is how the PiCam looks plugged into the eyepiece port on the back of my telescope, and also plugged into the serial port of my telescope’s mount. In this picture, the PiCam is the transparent plastic box at the center. The other camera with the gray cable at the top is the guiding camera I use when taking long exposure astrophotographs.


Remotely Connecting to the PiCam

The Pi is a Linux box, and it can run vncserver to export its desktop. You can then run a vnc client package, like the free TightVNC, on any other computer that is networked to the Pi. This is a screen shot taken from my Windows PC of the TightVNC application displaying the PiCam’s desktop. Here, the PiCam is running Mathematica and has imported a shot of the Moon’s limb from the camera module attached to the telescope via the adapter described above.


It’s hard to read in the above screen shot, but here is the line I used to import the image from the Pi’s camera module directly into Mathematica:

"!raspistill -ss 1000 -t 10 -w 1024 -h 1024 -o -",

This command invokes the Pi’s raspistill camera utility and captures a 1024×1024 image exposed at 1,000 microseconds after a 10-second delay, and then brings the resulting JPEG file into Mathematica.

One problem that I haven’t solved is how to easily focus the telescope remotely, because the PiCam’s preview image doesn’t work over the vnc connection. One interesting possibility would be to have Mathematica take a series of exposures while changing the focus via a servo attached to the focus knob of the telescope.


Mathematica and the Wolfram Language provide powerful tools for a wide variety of device control applications. In this case, I’ve used it on several different platforms to control a variety of astronomical hardware.

Pololu 9V, 2.5A Step-Down Voltage Regulator D24V25F9

via Pololu - New Products

This small synchronous switching step-down (or buck) regulator takes an input voltage of up to 38 V and efficiently reduces it to 9 V. The board measures only 0.7″ × 0.7″, but it allows a typical continuous output current of up to 2.5 A. Typical efficiencies of 85% to 95% make this regulator well suited for powering moderate loads like sensors or small motors. High efficiencies are maintained at light loads by dynamically changing the switching frequency, and an optional shutdown pin enables a low-power state with a current draw of a few hundred microamps.

Pololu 7.5V, 2.5A Step-Down Voltage Regulator D24V25F7

via Pololu - New Products

This small synchronous switching step-down (or buck) regulator takes an input voltage of up to 38 V and efficiently reduces it to 7.5 V. The board measures only 0.7″ × 0.7″, but it allows a typical continuous output current of up to 2.5 A. Typical efficiencies of 85% to 95% make this regulator well suited for powering moderate loads like sensors or small motors. High efficiencies are maintained at light loads by dynamically changing the switching frequency, and an optional shutdown pin enables a low-power state with a current draw of a few hundred microamps.

Christmas shopping guide

via Raspberry Pi

Christmas is coming, and we’re all panicking because we haven’t bought all the presents yet. (My Dad’s difficult.) Waking up at 3am in a cold sweat because you don’t know what to buy the Raspberry Pi fan in your life? Sweat no longer: we’re here to help!

Raspberry Pi kits

If you want a Raspberry Pi on its own, you can buy it from one of our manufacturing distributors, from our Swag Store, and from many other vendors.

There are also some great kits available if you want to get all the extra bits and bobs you’ll need in one box. We sell a starter kit containing a lot of goodies: it’s £75.


If all the extras in there make things a bit rich for your blood, check out The Pi Hut’s kit, which doesn’t have the shiny PiBow case, the special bag, the stickers or the keyboard or the mouse, but has everything else you’ll need. It’s £42.

Specialist starter kits for people wanting to use their Pi as a media centre, or focusing on using the camera board, are available from CPC in the UK, or MCM in the United States.


There is now a terrifying number of books available on the Raspberry Pi – check out the electronics or computing section of your local bookshop. Some of our favourites are:

The Raspberry Pi User Guide – this book’s written by our very own Eben Upton and by Gareth Halfacree; it’s the canonical guide to the Raspberry Pi, from the person who created it. This link goes to the latest edition, which covers things we’ve done this year like the Model B+.


Sticking with the “books wot we wrote” theme, here’s Carrie Anne’s Adventures in Raspberry Pi. Aimed at kids aged 11 and up (younger kids will still get a lot out of it, but we recommend Mum or Dad lends a hand), we think it’s the biggest seller of the Raspberry Pi books so far this year; and we highly recommend it.


If you’re an adult who doesn’t mind the branding, Raspberry Pi for Dummies is a superb guide to the device and what you can do with it. It’s good for beginners, but it’ll take you a long way – much further than you might guess from the title!


You can find many, many more Pi books at Amazon.

Add-on boards and fun

One of my favourite add-ons of the year was a late entrant: it only came out last week. Pimoroni’s Skywriter is a motion and distance sensor HAT for your Pi – and you can do this sort of thing with it (click the button to turn the sound on). It’s £16.

Pimoroni’s other add-on boards are among our very favourites: Pibrella is only £10, and offers you lots of inputs and outputs; we use it a lot in our own teaching sessions. It’s a fantastic way to get started with electronics: it’ll allow you to make noises, flash lights, drive motors and much more.


The Unicorn HAT is just magic. And it’s £18. That’s all we have to say about it.

Babbage the Bear is our mascot, and he’s had a very busy couple of years, going to near-space, having a camera stuck up his bum and becoming an Internet of Things device, and being cuddled by lots of small children. You can buy him at our Swag Store. He’s £9.


Today, we’re launching a NEW accessory for Babbage: the Babbage Backpack Game Kit. For £8.10 you can buy a cute little backpack for Babbage, filled with everything you’ll need to make an electronic memory game and instructions (no soldering required) – a perfect stocking-filler and a really great little project for electronics beginners. Plus, it makes Babbage look super-chic.




Ryan Walmsley set up his own business to make and sell electronics more than a year ago, and he’s still only 18. The RyanTeck Budget Robotics Kit is fantastic – it’s affordable at only £24.49, and contains everything you need to get started with robotics – all you need to add is a Raspberry Pi.

Pi&Bash is another new offering, this time from Piventor. THIS BOARD REQUIRES SOME SOLDERING, so it’s not ideal for first-timers. But it’s really good fun if you do fancy getting the soldering iron out, with traffic light LEDs, push buttons, a little backlit LCD screen, a thermometer, and digital and analogue inputs and outputs. It’s only £23.



The CamJam EduKit is the perfect stocking filler at only £5. It’s available from The Pi Hut, and it’s my absolute favourite learning kit of the year, coming bundled with worksheets to get you building electronics projects from scratch – or at least it was until the CamJam EduKit 2: Sensors came out last week, for a simply ridiculous £7. The Sensors kit contains everything you need to make a bedroom burglar alarm, a tea-temperature-tester, a device to test whether the light in your fridge really goes off when you shut the door, and much more, with worksheets. It’s a wonderful, wonderful, versatile little kit, and we think that the CamJam team and The Pi Hut have done an amazing job in getting it out for such an affordable price.


Finally, for those not worried to get a soldering iron out (soldering is easy – it’s really worth having a go), you can get an entire Christmas tree for your Pi for only £6. I saw several of these in action at the Cambridge Raspberry Jam last weekend; great for a festive addition to your workbench. Here’s one on a Model A+.

treeMerry Christmas!

Pololu 6V, 2.5A Step-Down Voltage Regulator D24V25F6

via Pololu - New Products

This small synchronous switching step-down (or buck) regulator takes an input voltage of up to 38 V and efficiently reduces it to 6 V. The board measures only 0.7″ × 0.7″, but it allows a typical continuous output current of up to 2.5 A. Typical efficiencies of 85% to 95% make this regulator well suited for powering moderate loads like sensors or small motors. High efficiencies are maintained at light loads by dynamically changing the switching frequency, and an optional shutdown pin enables a low-power state with a current draw of a few hundred microamps.

Pololu 3.3V, 2.5A Step-Down Voltage Regulator D24V25F3

via Pololu - New Products

This small synchronous switching step-down (or buck) regulator takes an input voltage of up to 38 V and efficiently reduces it to 3.3 V. The board measures only 0.7″ × 0.7″, but it allows a typical continuous output current of up to 2.5 A. Typical efficiencies of 80% to 95% make this regulator well suited for powering moderate loads like sensors or small motors. High efficiencies are maintained at light loads by dynamically changing the switching frequency, and an optional shutdown pin enables a low-power state with a current draw of a few hundred microamps.

New Product Friday: Dial ‘R’ for Resistance

via SparkFun Electronics Blog Posts

Hello everyone! I’m back and this is a great week for new products. We have a ton of cool stuff this week and there should definitely be a little something for everyone. Oh yeah, and the studio got a facelift!

Over the next few months we’ll continue to tweak the studio. Don’t worry, this isn’t its final form. We still have some acoustical corrections and more, so stay tuned. Let’s check out the list of products for this week.

SparkFun Decade Resistance Box

In stock KIT-13006

This is the SparkFun Decade Resistance Box, an involved PTH soldering kit that allows you to quickly and accurately dial in a…

$ 29.95

Have you ever needed a specific resistor value and didn’t want to go digging through parts bins? You might be interested in our decade resistance box kit. A decade box is a tool that contains resistors of many values accessed via mechanical switches. Adjust the knobs to output any of the discrete resistances offered by the box. Simply adjust the various knobs, and you can use this tool to substitute any resistor value you want. They are known as decade boxes because they have controls that correspond to the digits in a decimal number - a control for the ones position, a control for the tens position, a control for the hundreds position, and so on. Be warned, this kit requires a lot of soldering.

tinyESC v2 - Brushed Speed Controller

In stock ROB-13204

This is the tinyESC v2 from [FingerTech Robotics](, an ultra small bi-directional brushed …

$ 34.95

The tinyESC v2 from FingerTech Robotics is an ultra small bi-directional brushed motor controller for driving equally small DC motors. Don’t let the tinyESC’s size fool you, with the ability to take in a battery voltage of 6.5V to a whopping 36V and output a continuous current of 1.5A (3.0A peak), this little guy isn’t messing around! What it lacks in size, it makes up for in features. It has reverse polarity protection, overvoltage protection and even a battery eliminator circuit (BEC). This is the perfect speed controller for your ant or bettle weight robot!

Super-Awesome Sylvia’s Super-Awesome Project Book

Out of stock BOK-13232

Guess what?! Super-Awesome Sylvia, star of [Super-Awesome Sylvia's Super-Awesome Maker Show]( has a ne…

$ 14.95

Guess what?! Super-Awesome Sylvia, star of Super-Awesome Sylvia’s Super-Awesome Maker Show has a new book for young makers! It’s called, “Sylvia’s Super-Awesome Project Book: Super Simple Arduino!”. The book is a fun and colorful introduction to Arduino microcontrollers and programming, written and illustrated by kid engineer Super-Awesome Sylvia.

Sylvia's Super Awesome Arduino Kit

Out of stock KIT-13125

This is Sylvia's Super Awesome Arduino Kit, a companion kit for [_Sylvia’s Super-Awesome Project Book: Super Simple Arduino…

$ 29.95

We’ve also developed the Sylvia’s Super Awesome Arduino Kit that includes all the parts needed to complete the experiments in the book. As Sylvia says, “Get out there and make something!”

Crimping Pliers - 28-20 AWG

In stock TOL-13193

These crimping pliers allow you to easily make your own wiring harnesses using crimp pins and cable housings. We really like …

$ 29.95

These crimping pliers allow you to easily make your own wiring harnesses using crimp pins and cable housings. These pliers have a nice ratcheting action and a solid feel. They’re good for most smaller wire crimping applications.

E-Textiles Battery - 110mAh (2C Discharge)

In stock PRT-13112

This is a very small, extremely lightweight battery based on Polymer Lithium Ion chemistry. This is the highest energy densit…

$ 6.95

If you want to power your e-textiles product, you might not want a high discharge LiPo battery sewn into your clothing. That’s why we offer a battery specifically designed for wearables. It’s a lot like our standard 110mAh battery, but it has a specially designed protection circuit that cuts out at around 2C (or 240mA). This makes it safe for applications where conductive thread might accidentally short.

Solder Vacuum

In stock TOL-13203

The Solder Vacuum, a great (and sometimes under appreciated) little tool for solder rework. It allows you to pull the molten …

$ 4.95

I have to admit, this next product sucks. It’s true. Press the end of the plunger down, put it next to your project, and suck out the solder that’s not supposed to be there. Solder suckers are essential for desoldering components. This solder vacuum has a black metal body with a hard plastic nozzle and buttons.

SparkFun RFID Starter Kit

In stock KIT-13198

This it the SparkFun RFID Starter Kit, an all-in-one kit that offer everything you need to get your next RFID project off the…

$ 49.95

The SparkFun RFID Starter Kit is an all-in-one kit that offer everything you need to get your next RFID project off the ground. This kit includes our USB RFID Reader, ID-12LA RFID module, and two 125kHz RFID cards. This new version comes in a standard red box, instead of the plastic clamshell.

Alligator Clip with Pigtail (4 Pack)

In stock CAB-13191

This is a 4 pack of wires that are pre-terminated with an alligator clip on one end and a hookup pigtail on the other. Alliga…

$ 2.95

This is a 4 pack of wires that are pre-terminated with an alligator clip on one end and a hookup pigtail on the other. Alligator clips are a staple part for any workbench and with these cables you will be able to easily incorporate those clips into a breadboard, development platform, or anything else that you would normally be able to attach a hookup wire to.

E-textile Basics Lab Pack

Only 8 left! LAB-13165

This is the E-textile Basics Lab Pack, a basic wearables learning kit that can easily get you and a group of peers or student…

$ 199.95

The E-textile Basics Lab Pack is a basic wearables learning kit that can easily get you and a group of peers or students into the the world of e-textiles without having to deal with any programming or code. With this kit you will be able to learn how to sew in a variety of LEDs and other basic electronics into any fabric, power them, and make them twinkle within a few minutes!

Hack Pack Workshop Supply Kit

Only 3 left! LAB-13117

The Hack Pack Workshop Supply Kit is a great way to get your hackerspace, classroom or communal workshop stocked with basic t…

$ 574.95

The Hack Pack Workshop Supply Kit is a great way to get your hackerspace, classroom or communal workshop stocked with basic tools! Each Hack Pack includes a few hand tools like pliers and diagonal cutters as well as a few variable heat soldering irons and the necessary accoutrement. Also included? screw drivers, shrink tube, the legendary Heaterizer XL-3000 heat gun, third-hand, solder, and of course a few pairs of SparkFun Safety Glasses!

Screw - Phillip Head (M3 x 12mm, 3 pack)

In stock PRT-13227

These are Philips-head M3 screws. They are 12mm long and come in packs of three. This is the screw size that the MiP robotic …

$ 0.95

We now carry a 3-pack of screws that work with the MiP robotic platform proto boards. If you want to attach either the Proto-Pack or the Proto-Back boards to your MiP, you’re gonna need 3 screws to do so.

That’s it for me. That’s all the new stuff we have for this week. Thanks for watching and reading. We’ll be back again next week with more new stuff, don’t worry! See you then!

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Arduino TRE Developer Edition, 2nd round of beta-testing

via Arduino Blog

Arduino TRE

30 Arduino TRE Developer Edition boards (the last ones!) are available online today on our store. Whoever purchases them will be added to our Beta-testing Program, joining the about hundred betatesters already contributing to the development of the hardware and software of the board. You can learn about the program and the board on this post.

These boards have the latest Web IDE pre-installed and ready to go, we are now at a stable IDE release with everything fully functional. We will write a specific post about the new Web IDE next week, so stay tuned!

The first round of the program focused mostly on hardware and software testing, and we have just rewarded the betatesters who contributed the most. We really would like this second round to revolve around contents creation. For all Arduino boards, examples and projects are really crucial to get beginners started with a new environment. This is even more relevant for the Arduino TRE, that thanks to the onboard Linux system, has so much more power and potential than classic Arduinos.

For instance you could use the Arduino TRE as a personal cloud, keeping all your data available to your connected devices without having to rely on third party services; you could create a system to stream music wirelessly to your speakers with a tangible user interface; build a DIGI software that allows ZigBee porting; make an interactive whiteboard for schools, and so on.

We have a reward system in place for completed projects: two coupons of the same value of the Arduino TRE Developer Edition purchased, a dedicated post on our blog, Arduino TRE limited edition T-shirts, 10% off coupons for the Arduino Store. We look forward to hear about your projects!

When is the Arduino TRE going to be finally on the market? The board is ready, but we don’t have a final release date yet because we are still figuring out some manufacturing matters. We’ll keep you posted!


An example of a project running on an Arduino TRE.
3D Photobooth, Xun Yung and Tien Pham, Maker Faire Rome 2014.
A 3D anaglyph photobooth uses two cameras to capture a 3D picture. Each picture is processed using the Arduino TRE board. It separates the red channel from one camera and the cyan channel from the other, and overlays them together. The result is then printed out on a large photostrip.

Arduino Gift Guides that fit anyone’s piggy bank

via Arduino Blog

Xmas Banners-18

Last week we published our gift guides presenting you a list of products  available on the Arduino Store and divided by topic for Kids and people interested in IoT, Home Lab and Fashion Tech.

Now we’d like to give you some suggestions for gift ideas fitting anyone’s piggy bank:

Gifts Under 15€

Arduino ISP

It’s a tiny AVR-ISP (in-system programmer) based on David Mellis’ project FabISPand useful to anyone needing more space on the Arduino board



Flashing Card Set – Merry Resistivities by Bare Conductive


The Merry Resistivities Set contains all the materials you need to make three flashing greeting cards using Electric Paint. This fun activity is great for makers of all ages.


Minipov by Adafruit


A simple POV toy for beginners who are looking to learn how to solder, how to program microcontrollers, or make LED blinky toys. Because the programmer is built into the kit, one does not need a special “microcontroller programmer”.

Arduino Proto Shield


The Arduino Prototyping Shield makes it easy for you to design custom circuits for your next Arduino project. You can solder parts to the prototyping area to create your project with extra connections for all of the Arduino I/O pins.


Make Robot Notebook Moleskine


Pocket Moleskine Notebook – Fresh from the Maker Faire comes our exclusive mini-Moleskine (5.5″x3.5″, 30 pages) notebook, available with Robot logos.


Gifts Under 30€

Getting Started with Arduino – 2nd Edition


This classic book to start tinkering with Arduino gives you lots of ideas for projects and helps you work with them right away. From getting organized to putting the final touches on your prototype, all the information you need is here!


Arduino Case + Breadboard Wires Kit


This lasercut (in Officine Arduino), wooden case is perfect to host your project and store electronic parts. It features two drawers, a confortable surface for a standard breadboard and the space for two Arduinos to be hooked up. It’s stackable, perfect for teaching material or group work.

Arduino UNO


If you want to make any beginner happy, this is the perfect gift. “Uno” means “One” in Italian and is named to mark the upcoming release of Arduino 1.0. The Uno and version 1.0 will be the reference versions of Arduino, moving forward. The Uno is the latest in a series of USB Arduino boards, and the reference model for the Arduino platform.


Lumi Red or Blu


Lumi is a new DIY alternative to screen printing.The process works on cotton, linen, silk, rayon, canvas, and any other natural & absorbent fiber. Once finished, your print is permanent and can be machine washed without fading.


Blend Micro by RedBearLab


Arduino At Heart Blend Micro is RedBearLab first integrated developement board, they have “blend”ed Arduino with Bluetooth 4.0 Low Energy (aka BLE or Bluetooth Smart) into a single board. It is targeted for makers to develop low power Internet-Of-Things (IoT) projects quickly and easily.


Gifts Under 60€

Arduino Esplora


The Arduino Esplora is a ready-to-use, easy-to-hold controller that lets you explore the infinitive possibilities you have in the world of sensor and actuators, without having to deal with breadboards, soldering or cable. There is no limits to the sensors applications! Adding a LCD module you can make your personal videogame!


Bare Conductive Touch Board


Touch Board can turn almost any material or surface into a sensor by connecting it to one of its 12 electrodes, using conductive paint or anything conductive. It’s designed as an easy-to-use platform for a huge range of projects, whether it’s painting a lightswitch on your wall, making a paper piano or something nobody’s thought of yet.


Intel Edison


The Intel Edison is an ultra small computing platform that will change the way you look at embedded electronics. This kit also includes a Arduino Breakout, which essentially gives your Edison the ability to interface with Arduino shields or any board with the Arduino footprint.


Arduino Yún


Arduino with onboard Wi-Fi connectivity and a Linux computer. Great for IoT projects. The Arduino YÚN is the combination of a classic Arduino Leonardo (based on the Atmega32U4 processor) with a WiFi system-on-chip running OpenWrt-Yun.



FREE SHIPPING to European Union for all orders over €100 (below 3Kg overall weight). Should you need delivery by Dec 24th, we strongly advise you to place the order before Dec 15th. FREE SHIPPING is available from Dec. 2nd 2014 until Jan 6th 2015. Read more about the shipping policy.

Enginursday: Favorite Tools

via SparkFun Electronics Blog Posts

As I threatened last spring, I have a lot of different sets of wire strippers hanging around, and I’m going to do some show-and-tell about them here today. Having done a lot of wiring-intensive work (like wiring up recording studios), I eventually found that having good tools makes the task much easier, and improves the overall quality of the work.

We’ll run somewhat chronologically through my collection here. It’s interesting to note that they’re organized in order of acquisition, but that also matches (more or less) how expensive they are. Like many hobbies and careers, as I got deeper into electronics, I found I needed tools of higher quality, with more specialized application.

The Cheap Ones

This is my oldest set of wire strippers.

Just Say No

They’re more a source of frustration than of elegantly stripped wires.

As we discuss in the Working with Wire tutorial, when you strip wire, you want to remove the insulation, but leave the wire underneath intact. You don’t want to nick the copper, which weakens the wire - eventually it will fatigue and snap, right where it got nicked. If you’re working with very fine stranded wire, it might also leave a little fuzz of strands at the end of the insulation, which could lead to short circuits. So the most important thing wire strippers can do is cut insulation, and leave the wire unscathed. These strippers fall down on that point.

To casually inspect them, they look like a good idea - the set screw in the slot should allow you to set the gauge of wire to strip…but it isn’t meaningfully calibrated. Trying to set it involves testing it a bunch of times. Then, once it’s set, the set screw slips, and always down the handles, so the opening gets smaller, inviting them to nick the copper.

The other major problem is that the hole in the jaws is square. We’re stripping round wire with a square hole, again likely to nick the underlying copper.

There’s a timeframe early in my project history where the primary failure mode is directly tractable to the exact pair of wire strippers pictured above.

The Daily Driver

After wrestling with the cheapies for way too long, I upgraded to a real wire stripper - the ones that look like a pair of pliers with a set of graduated holes for different gauges.

Better Strippers

Here are three examples of regular wire strippers, including the ones that replaced the cheapies, plus our SparkFun-branded ones, and our somewhat nicer Hakko strippers.

They’re the ones I’ll reach for for general purpose work, such as dealing with hookup wire.

Functionally, these are all very similar. The things that makes them more useful than the cheap ones:

  1. The holes to strip the wire are round, just like the wire!

  2. The real trick is that they stop mechanically before the holes actually get down to the size of the copper - they’re just a tiny bit larger, so they only cut the insulation.

I’d imagine that these meet the needs of the average electronics student or hobbyist. But to explore the topic more completely, I’m going to pull up a few more esoteric sets.

Special Purpose Strippers

The general purpose strippers above are good on my electronics workbench for day-to-day prototyping needs. But they’re somewhat limited - for example, the Hakko’s are sized for 20 to 30 ga wire. If I’m working with larger wire, or fancier wire like sheathed multipair audio or control cable, they’re not always a good fit.

Household Wiring

In north America, household AC wiring is done with a bundled cable that’s sold under the brand name Romex. It has three conductors (hot, neutral and ground) arranged side-by-side in a common sheath, with an oblong profile. It’s most commonly available in solid-core 12 and 14 AWG.

It’s larger than anything on my electronics workbench, and the strippers shown above aren’t terribly effective for it. Even if they could handle 12 or 14 ga cable, removing the outer jacket just to get to the inner wires is pretty tedious. It calls for it’s own special tools.

alt text

This Klein stripper is made specifically for handling Romex. It is features a two-step stripping process. The first step uses dumbbell shaped holes that remove the jacket, but leave the inner conductor insulation intact. Once the jacket is removed, it has single 12 and 14 AWG sized round holes to strip the inner conductors.

The handles also appear to be double coated - this is to make the handles more comfortable to grip - don’t confuse it with being insulated against electrical shock! Klein themselves state:

NOT insulated. Plastic-dipped or slip-on plastic handles are NOT intended for protection against electrical shock.

For safety’s sake, don’t work on live circuits. Shut off the breaker, and as a double-precaution, use a live-wire detector, as shown above, to make sure it’s off. And as a triple precaution, check the live wire detector on an actual live circuit, just in case the batteries are dead!

Getting Warmer

In wiring up recording studios, a lot of the wiring is often custom fabricated on site. It usually involves many lengths of multipair cable, such as Redco TGS or Mogami Snake Cable.

Working with these requires several layers of stripping.

The outer layer is almost like garden hose, and can be removed carefully with a razor blade.

Inside that are a number of pairs of cables, each about 3/16" thick. To strip the pairs without damaging the interior wire, I use a thermal stripper.

alt text

This is a Teledyne Stripall. When you press the red button, the blades on the end heat up, to melt through the insulaton. You heat them up, then pinch and twist, and the insulation comes right off. The blades themselves are blunt - there are no sharp edges to scar the internal conductors.

The Teledynes aren’t the only thermal stripper around, they’re just the set I have on my bench. Patco Inc make a similar hand-held stripper with a single, fixed, v-shaped blade, and Hakko make a set with a lightweight handle tied to a base station, similar to their soldering stations.

The (absent) Co-Ax Stripper

It seems like some tools have a life of their own. They wander around, and they’re never where I remember using them last. My little co-ax stripper seems to be bashful, and didn’t make it to the photoshoot. I’ll try to describe it, instead - it’s essentially a razor blade with some depth stops, and a loop for your finger. You insert the cable into a notch, then spin the stripper around the cable, so the razor can cut the jacket.

You can find them at the hardware store - they’re usually found with the cable TV parts - and possibly included for free in the box if you buy a whole spool of 75 Ohm cable!

Simple ones just have a set of different depth stops molded into the plastic - you put the wire into the notch that cuts the insulation, but not the conductor. There are different ones for different types of wire - RG-6 or RG-59 TV Cable being the most common. Fancier ones have adjustable depth stops, and even fancier ones have multiple blades that can strip the outer jacket and inner insulation all at once, neatly measured to fit a crimp-on connector.

The adjustable ones are also useful for other types of cable, including audio and instrumentation cable.

Cleaner and Faster

Once the jacket on an audio snake cable has been removed, and the second layer on the pair stripped, the individual wires need to be stripped. The underlying wire is really fine - TGS is stranded 26 AWG, composed of 40 strands of 30 AWG. If you’re even a little overzealous with the strippers, the inner conductors are severed, making coppery angelhair on your workbench. It calls for a more precise tool.

alt text

This is an Ideal Industries Stripmaster. The business end has replaceable blades that look somewhat like the the graduated holes in the regular wire strippers, but the overall mechanism makes them more precise.

There are actually several mechanisms in these strippers, all actuated by squeezing the handles.

  1. When you first squeeze the handles, a clamp in the jaws closes, holding the wire exactly where the cutting blades will meet it.
  2. After the clamp is closed, the blades close around the insulation, just piercing it.
  3. As you squeeze harder, the blades and the clamp move away from each other. The insulation is cleanly plucked off the wire.
  4. When the handles meet each other, a lever catches, so that the actions are reversed as the handles are released.
  5. As you relax the handles, the blades and clamp release the wire, before the mechanism swings shut, so you can pull the wire out before they close.

It sounds like a lot of detail to be aware of - but in practice, it’s all done in the blink of an eye.

There are a few of things to be aware of if you’re using a Stripmaster.

First, if you’re using one of these, and it’s smashing the stripped wire when you release the handles, make sure that you’re squeezing the handles completely - if you don’t complete the cycle, the lever that opens the clamp before the jaws close won’t catch. It’s one of those situations where trying to take a shortcut really doesn’t pay off.

Second, if you’re seeking out one of these strippers, it’s important to note that they’re sold with blades suited to different wire sizes. The average hardware store will have blades for household wiring, in the 10 to 16 AWG range. But those aren’t the only blades. The set shown above have 20 to 30 AWG blades, perfect for small electronics work, and there are other sizes in between, including blades specifically made for RG-6 and RG-59. The blades are interchangeable and sold separately, so you could reconfigure one set for different wire by swapping blades.

Finally, the action of the stripper can cause the machine screws that hold the blades to loosen, and the blades can become misaligned. You’ll want to remember to tighten them periodically, or hit them with a dot of Loctite.

An Incomplete Survey

These are just the wire strippers I use on a regular basis, and not an exhaustive listing. I’m sure I’ve missed someones favorites - perhaps even tools that I’d find handy. What are your favorite wire strippers?

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