It’s not everyday that we review software around here, but the folks at Adafruit recently put together an iOS app that I figured might be of interest. Their iPad/iPhone compatible application is called “Circuit Playground”, and it includes all sorts of handy electronics reference tools. For the context of this review, it should be noted that I paid for the application myself, and that I have had no communication with the Adafruit team regarding my assessment of the app.

As you can see from the main screen, the app currently features eight different tools, not counting the “Deals @ Adafruit” entry, since I consider that to be more of a marketing strategy than a real tool. The rest of the items are pretty standard reference fare, in an easy to use and understand package.

The Resistor Value tool is pretty straightforward, allowing you to specify resistance in two ways. You can select the color bands of your resistor and view the resulting value, or enter the resistance to see what color resistor you should be looking for. It supports both 4 and 5 band resistors as you would expect, and features a simple “Instruction Page” (as do all the tools), accessible via the small information icon on the bottom left corner of the screen. One thing I would love to see implemented is the ability to photograph components and display their resistance. I think it would be a very helpful addition for makers whose eyesight isn’t what it used to be.

The Multiple Resistor and Multiple Capacitor tools are similar in function, showing you the resultant resistance/capacitance of various series and parallel component setups. They both support up to 9 items apiece, and let you select the capacitance and resistance values for each component one at a time. This is both good and bad, as it gets pretty tedious entering each value manually after a bit. One other item that I thought could use improvement here was the functionality of switching between series and parallel configurations or adding/removing components. Any time a change is made to the configuration, all of the values are reset – this means that if you add another resistor to your 8-resistor diagram, you must re-enter each and every value.

The LED Resistor Calculator does exactly as its name suggests, much like many online calculators that have come before it. This handy feature lets you pick your LED color from a pre-determined list, populating the forward voltage and current fields automatically, based on some common/standard values. Once you specify a supply voltage and quantity of LEDs, the application returns the exact resistance required to meet your specs, along with the value of the nearest standard resistor. While the tool is certainly helpful when calculating resistors for LEDs in series, it lacks any sort of ability to do the same for parallel configurations. If the folks at Adafruit included that functionality along with the ability to customize the default LED list, I would be thrilled. I do have to point out however, that this tool does retain the LED count and supply voltage when changing LED colors, which is something I was glad to see after playing around with the Multiple Resistor tool.

The Ohm’s Law calculator is a simple tool that is great for allowing me to carry out quick sanity checks of the math I have done in my head. Simply enter two values in the triangle, and Circuit Playground spits out the third. The Power Calculator is a similarly straightforward tool, which takes in two of four values (Power, Voltage, Current, Resistance), calculating the rest for you. Neither tool is overly complicated, but then again they don’t need to be.

The final calculator that the app provides makes number conversions dead simple. Given one number, the converter will give you its representation in binary, decimal, hexadecimal, octal, and ASCII notation. While it might not be something that I’ll use every day, it certainly is a very helpful reference tool. I personally think that this tool would benefit from the ability to convert strings of characters/numbers rather than one at a time, but perhaps that is something they are looking to add in a forthcoming release.

One of Circuit Playground’s features that is not as prominent as the others on the main menu is the built-in datasheet viewer. It uses a lightweight interface to help search through and view PDF files located in the iPhone’s document store. I don’t have anything of the sort stored on my phone so I can’t truly test this portion of the app – let us know in the comments how it works for you.

A few data persistence nitpicks aside, I think that Circuit Playground is a solid app with a lot of potential. At $2.99 it sits at the higher end of the App Store pricing structure, so whether or not these tools are worth it is ultimately up to you. Adafruit does say that anyone who purchases the app gets $3 off their next order in their online store, which essentially makes the app free if you are a regular customer.

While it’s not designed for your seasoned Electrical Engineer, it is definitely a great resource for the part-time tinkerers out there. At the moment, it is an iOS-only offering, but Adafruit says that they will be releasing an Android version at some point in the future. In the meantime, they suggest giving ElectroDroid a try, as it is currently the best app on that platform.

There is a plethora of electronics tutorials scattered about online. Sometimes it can be hard to separate the good ones from the bad, and the enlightening from the misinformed. We recently came across a pair that we found helpful, and thought they would appeal to anyone starting off in electronics.

In this video tutorial, [Dave Jones] at the EEVblog covers soldering, detailing good practices and common mistakes to avoid when working with through-hole components. As the second video in a series he picks up where part one left off, excitedly demonstrating the ins and outs of good soldering skills.

Hackaday reader [grenadier] is working on a series of beginner’s electronics tutorials, and this week’s entry covers wiring. He discusses wire types, gauges, and even provides a nifty self-computing chart that calculates power loss based on the length and gauge of the selected wire. Before wrapping things up, he briefly touches on fuses and the pitfalls of choosing wire that’s not up to the task at hand. While you’re over there looking over his tutorial, be sure to check out the Junkbox, there’s plenty of awesome stuff to be had!

Hackaday reader [grenadier] wrote in to share a series of tutorials he is working on, where he discusses the basics of electricity and electronics. The first lesson titled, What is Electricity?” has been wrapped up, and is available for free on his site.

For any of our regular readers, the lesson will seem pretty basic (and likely full of things to nitpick). However, we imagine his lessons would be quite helpful to anyone looking to expand their electronics know-how.

Now don’t get us wrong, we love the series of electronics tutorials that Jeri has been periodically releasing, but we think there’s plenty of room on the Internet for other willing teachers as well. If his first lesson is any indicator, his tutorials will be easy to understand, sprinkled with a little bit of humor, and chock full of fun videos that demonstrate the subject at hand.

Take a quick look his way if you get a chance – you or someone you know might find his tutorials and reference guides insightful.

[Image courtesy of Electronicsandyou]

[Kenneth] is a Mechanical Engineer who likes to dabble in electronics. Besides providing us with an excellent picture of his workbench, he has put together a list of things that you’ll need as you learn to work with electronics. A beginner electronics kit from one of a number of different sources may work for some, but others may not be interested in a kit.

[Kenneth] gives links and recommendations for categories of: books, electrical equipment, development tools, components, digital electronics, and analog chips. As he puts it, this post is a “gigantic list of everything I would buy right now to replace my entire workshop if mine were to disappear.”  This is a great list of things you may need if you’re starting out.  If you have some experience, this list may introduce you something new. Check out some of [Kenneth's] other projects like his cloud chamber or the Chumby webserver that he made.

[Windell] over at Evil Mad Scientist Laboratories has reached out in order to help them identify a mystery piece of electronics equipment they came across a few years ago. Discovered at an electronics surplus store, the mystery component looks like a cross between an over-sized chess board and a breadboard. Failing to identify it they eventually disposed of the board, snapping a couple of pictures for good measure before it was gone for good.

Recently while visiting a local electronics flea market, they came across what looked to be a similar, though much smaller board. This piqued their curiosity and compelled them to dig out the pictures of the mystery board in hopes of finally discovering what it was. Using markings on the new board they found, the team at EMSL located some images of a patchboard cartridge that looked quite similar to their mystery object. Upon closer inspection however, they think that the two pieces might be related, but are not quite the same item.

Swing by their site and chime in if you happen to have any good leads – we’re sure they will appreciate it.

[Aestetix] writes in to tell us that the OpenAMD (Attendee Meta-Data) project is working on a new revision of their hardware, to be debuted at CCC Camp this fall.

For the uninitiated, OpenAMD combines an Active RFID tracking system with social networking, and is completely open-source. You walk into the conference, put on the OpenAMD badge, and suddenly you can see yourself as a dot moving around on a map. Or you can log into the social networking site, create a profile, and watch as your personal information is pulled into the mesh, which then tells you talks you might like, people you might like, where those people are, and more. There’s even an open API where you can create your own ‘killer’ apps, which may include games or other interesting aggregates of the attendee information.

This year’s “erlenmeyer flask” badge is the latest incarnation of the project you may have seen at 2600′s Hackers on Planet Earth conference in 2008 and 2010, or at Chaos Computer Congress (CCC) in 2006 or 2007. This time, the team is looking to deploy at this summer’s CCC Camp, and at numerous conferences in the future to be determined.

The badge itself is an Atmega AVR microcontroller connected to a Nordic nRF24L01+ and a pair of 74HC595 shift registers. The AVR is running USBaspLoader with custom OpenAMD firmware on top, which in concert with the Nordic chip implements the OpenBeacon air protocol. The shift registers drive 14 LEDs which are capable of being used as a persistence of vision display. Because of the USBaspLoader, you don’t even need an Atmega in-circuit programmer to reflash the chip: You can even use the Arduino IDE to implement your own functionality.

The badges, the ‘readers’, all the hardware and software required to create your own instance is completely open source, and you can download the specs today and tinker with them.

So what’s the catch? They need your help. They’re running a kickstarter to raise the minimum amount needed to fabricate these badges and bring them to CCC Camp, and any support you can offer will go a long way to help. Even if you’re not going to CCC Camp, they’re planning at deploying at many more conferences state-side in the future, and the badges themselves are more than enough fun to tinker with. The Nordic chip can be particularly fun.

Here’s a short video explaining the whole thing from last year’s installation at TNH:

Full disclosure? I’m designing the badge hardware this time around.

[Ben] needed an input device that would operate where electrical signals and magnetic fields wouldn’t be tolerated, so he ended up running fiberoptics instead of electricity to a mouse.

[Ben] ran some glass fiber from the mouse to quadrature encoders to get the x and y velocity. Mouse clicks are read by modifying the existing buttons with a small shutter to block light from shining through the button frame. This isn’t the first time [Ben] adapted fiberoptics to an input device. Last year, he also built a fiberoptic joystick using the same principles.

We covered [Ben]‘s DIY Electron Microscope last month, and we’re wondering if these two projects are related. His project log said he was getting distorted images from the electric field coming from his cooling fan and heater. Maybe he solved that problem and is now just tracking down every last unwanted electromagnetic emission.

Video of the mouse after the break.

The 555 Design Contest shook a whole bunch of really creative circuits out of the trees, hence the 555-heavy content lately. While not technically part of the contest, [esalazar] wanted to know what made the 555 tick, literally! He started working on the project in a circuit simulator, then ultimately ended up building the three main logic blocks inside the familiar timer on pieces of copper-clad board. He’d built a 555 using discrete components.

While this isn’t 100% compatible with the classic 555 IC, it covers the basics pretty well, and [esalazar] gets extra-credit points for embracing the hacker spirit of seeing for himself how stuff works while documenting it well and citing his references.

Remember how fun it was studying chemistry and physics in high school? Well we guess your recollection depends on the person who taught the class. Why not have another go at it by learning the A-to-Z of electronics from one of our favorite teachers, [Jeri Ellsworth].

You know, the person who whips up chemistry experiments and makes her own semiconductors? The first link in this post will send you to her video playlist. So far she’s posted A is for Ampere and B is for Battery, both of which you’ll find embedded after the break. Her combination of no-nonsense technical explanation, and all-nonsense paper-doll history reenactment make for a fun viewing whether you retain any of the information or not.

[Thanks PT]

Gizmodo University is open for business. This free educational series aims to educate about the basics of electronic theory. No prerequisite knowledge needed and they’re starting from the ground level. First lesson? Resistors! From there they’ve posted about voltage dividers, series/parallel circuits, Ohm’s law, and how to calculate a resistor value for an LED.

This is a great way to get the base knowledge that you need to start hacking like an EE. These are concepts that we assume you have already mastered if you’re following along with our AVR Programming series. We’re hard at work on part three but that’s still a little ways off. You’ve got time to do a review a GizU and reread our favorite book on electronic theory.

We’ve been watching the development of the snega2usb since it’s debut on Hackaday. Now it’s grown up and is ready to be manufactured. In the low quality video above [Matthias] shows some of the latest high quality additions to the board. It now has a case, shiny new firmware,  production made PCB, and game pad ports.  The snega2usb is shipping this December for those who preorder now.

We’ve covered sequencers before, but reader [Johan] sent in his latest project that is much more minimalistic approach. Dubbed the BBox, he based his drum generator on an Arduino and an LCD display. Rather than synthesizing sound, the Arduino just outputs MIDI which is then interpreted by his Roland Juno-D. In building the device he used a favorite trick of ours to keep the interface clean. He then found an awesome banana box to use as a case. Although, the project may not be as functional as some of the others out there, it certainly has flair. Video of it in action after the break.

When we first posted [Matthias_H]‘s USB reader for SNES game carts, it was met with enthusiasm. The snega2usb allows you to play SNES and Sega games on your pc right off the cartridge. The latest revision is even more amazing than the first.  [Matthias] has added the ability to read Sega Genesis/Mega Drive cartridges as well as the ability to save games directly to the cartridge. The board has also been updated from the rats nest it used to be to a smart looking dual sided PCB. So far [Matthias] hasn’t had any trouble reading cartridges, even ones with the SuperFX chips. [Matthias] also launched a site for the project where the lastest information on its development can be found.  [Matthias] is getting close to a production version which will feature better firmware, console quality connectors and a shiny case.

[Sebastian Tomczak] was borrowing a homeade muon detector from his friend, and managed to hook it up to his computer through an Arduino. The detector itself uses 3 fluorescent tubes to detect radiation. Three separate tubes are used in order to filter out terrestrial radiation; cosmic radiation will fall in-line with the tubes and pass through at least two of them, whereas terrestrial radiation will only hit one. There is some basic circuitry to amplify the signal and then perform the OR operation.

[Tomczak]  used an Arduino to take the raw data and feed it into his computer. He then used Max/MSP to analyze the data and filter out background noise, leaving only the cosmic ray data. He didn’t mention what he was going to use the data for, though. Maybe he’ll hook it up to a synthesizer.

Related: Digital Geiger counter

[via @littlebirdceo]

There are so many apps available for the iPhone, one might even say there are a plethora. We would like to take a moment to help you find a few that might help with your hacking projects. Ever have problems remember a formula when you need it? Need to track the acceleration of your brand new rover? How about beginners needing help remember resistor codes. Well, there’s an app for that. Check out our suggestions after the break.

Here at Hack A Day, we are strong believers in frugality. We think most hackers are. With that in mind, lets start off with our recommendations of free applications to get the job done. These are in no particular order.

The iPhone camera: Not only is this free, its already on your iPhone. yeah, we know its not a great camera, but it is indispensable. Taking apart a project? Snap some pics along the way so you can refer back to them when you reassemble. Project ready for testing? Document it quickly and easy with pictures. Project burst into flames on the tarmac? Snap a pic for posterity. We love the camera.

Electrical toolkit: Even the most experienced hackers need a little help  sometimes. Need to find the SCR Firing angles this app can help with that.

Electronics toolkit: Another app meant to help us find the missing pieces to a circuit. This one has some different circuits than the Electrical toolkit above.

iResist: Maybe you never committed the resistor codes to memory, or maybe you’re a beginner just learning. Either way, this appears to be a pretty useful application. Simply select the appropriate colors and it will tell you the value of your resistor.

ResistorCode: Another resistor code application. This one has the ability to do up to 6 band resistors. We listed both because some people really have a preference between the text selection or color selection. We like the more robust feature set of this one.

LED resist: Who hasn’t been left scratching their head when wiring LEDs? This handy little app will help you figure out what resistance value is needed to keep those LEDs functioning optimally.

Runkeeper free: Runners have been raving about this one for a while now. It will track your time, distance, GPS location, and speed. You can view your path on a google map. We’re not exactly sure what project would merit this, but it just seems perfect for tracking rovers or measuring experimental vehicle performance.

Though we do love the free applications, sometimes things just merit a little payment. We really only found 2 apps that we thought could be useful enough to pay for when it comes to hacking.

Formula Pro: We don’t care how l337 of a hacker you are. You simply can’t know everything. This application is a compendium of the most common formulas needed for Engineering, Optics, Thermodynamics, Electronics and much more. There are over 680 formulas out of the box, with features like the ability to modify and save formulas or even add your own. At 1.99, this is a steal.

Accelleration 3d detector: This feature rich acceleration detector will log and chart in 3d your acceleration information. You can even download the results to your computer for inspection. Though we have concerns about the destruction of our iPhone, this just seems like it would be a great tool in a pinch for finding out some acceleration data.

Lastly, we understand that no project goes perfectly. Sometimes you are so frustrated and your brain is so fried, you just can’t function. It is times like these that Bubble Snap comes to the rescue. There are no rules, just the soothing pleasure of popping bubble wrap. Careful though, your kids or significant others might get addicted to this one and steal your phone.

Well, those are our favorites. What do you use? Did we miss any? The iPhone is supposed support accessories with the latest iteration, are there any must have accessories for the hacker?