Monthly Archives: April 2018

Attiny wearable

via Dangerous Prototypes


Attiny wearable project from Facelesstech:

It’s a foundation for a wearable platform. It’s a Nato watch strap threaded through a PCB with a coin cell battery holder between the PCB and the strap. I’m using a Attiny85 this time around but could be used for most chips/dev boards. This is a proof of concept to iron out any problems I’ve overlooked.

Project info at Facelesstech’s blog and the GitHub repository here.

Check out the video after the break.

6 channel speaker selector

via Dangerous Prototypes


Dilshan Jayakody published a new build:

If you are an audio enthusiast and if you have multiple audio systems and speakers, you may definitely need to have a speaker selector switch. These switches allow you to route a audio signal through a switching system and distribute it to various speakers. Using this listener can select single amplifier – speaker combination through the switch. We mainly design this switch to share our speaker system with multiple audio amplifiers. We design this switch to handle 6 stereo audio channels.

See the full post on his blog here.  Project files are available at Github.

How to Model and 3D Print a Project Box

via SparkFun: Commerce Blog

Getting started with 3D modeling and 3D printing can seem like a daunting task, but it doesn’t have to be. The easiest place to start is with a simple shape, like a box. Additionally, it can help to create something useful (or at least marginally useful) to act as motivation.

Making a 3D printed project enclosure

Downloading a part from Thingiverse and printing it is a good place to start, especially if you want to test your printer or want something awesome that someone else has made. But what if you’re ready to start designing your own models? Where do you go? There are scores of 3D modeling programs out there, and some of them work better with 3D printing than others. Here are some of the ones I’ve had experience with:

  • Tinkercad - Free, web-based modeling software from Autodesk that’s great for beginners. Great for making models for 3D printing, but is limited in features.
  • SketchUp - There is a free (now web-based) and a paid (Pro) version. Easy to learn and use, but has trouble producing 3D printer-friendly models.
  • Fusion 360 - Full-featured modeling software also from Autodesk that’s free for students and hobbyists. Favored by many hobbyists.
  • SolidWorks - Full-featured CAD software that has a large professional following. Expensive.
  • Blender - Free and open-source modeling program with a steep learning curve.

If you are just getting started with modeling and printing, I highly recommend giving Tinkercad a shot. You can whip up simple designs in a matter of minutes. Do note that it is lacking some advanced features, like being able to add chamfers or fillets (you can technically subtract a round shape out of another shape and then use that to create a fillet on your design’s corners, but it’s a pain).

I’ve created a quick guide on getting started with Tinkercad. In it, I show how to design a box, import it into a slicer, and then print it. It’s a great starting place, especially if you’re looking to create custom enclosures for your electronics projects. That being said, it’s meant as a starting point; putting just a Pro Mini is box is a fairly useless exercise. Feel free to modify the dimensions to fit your own project!


Getting Started with 3D Printing Using Tinkercad

April 30, 2018

Tinkercad is a great, easy-to-use online modeling software that can have you 3D printing quickly. This tutorial will walk you through designing a simple project enclosure.

Also, the instructions for printing were written for a LulzBot TAZ 5 printer (now retired in favor of the TAZ 6), mostly because that’s what I had access to. Most of the LulzBot printers should work similarly, but if you have a different printer, you’ll want to follow that manufacturer’s guidelines for which Slicer program to use and how to print.

For those of you out there with more 3D printing experience, what other modeling or troubleshooting tips can you recommend?

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Scanning snacks to your Wunderlist shopping list with Wunderscan

via Raspberry Pi

Brian Carrigan found the remains of a $500 supermarket barcode scanner at a Scrap Exchange for $6.25, and decided to put it to use as a shopping list builder for his pantry.

Raspberry Pi Barcode Scanner Wunderscan Brian Carrigan

Upcycling from scraps

Brian wasn’t planning to build the Wunderscan. But when he stumbled upon the remains of a $500 Cubit barcode scanner at his local reuse center, his inner maker took hold of the situation.

It had been ripped from its connectors and had unlabeled wires hanging from it; a bit of hardware gore if such a thing exists. It was labeled on sale for $6.25, and a quick search revealed that it originally retailed at over $500… I figured I would try to reverse engineer it, and if all else fails, scrap it for the laser and motor.

Brian decided that the scanner, once refurbished with a Raspberry Pi Zero W and new wiring, would make a great addition to his home pantry as a shopping list builder using Wunderlist. “I thought a great use of this would be to keep near our pantry so that when we are out of a spice or snack, we could just scan the item and it would get posted to our shopping list.”

Reverse engineering

The datasheet for the Cubit scanner was available online, and Brian was able to discover the missing pieces required to bring the unit back to working order.

Raspberry Pi Barcode Scanner Wunderscan Brian Carrigan

However, no wiring diagram was provided with the datasheet, so he was forced to figure out the power connections and signal output for himself using a bit of luck and an oscilloscope.

Now that the part was powered and working, all that was left was finding the RS232 transmit line. I used my oscilloscope to do this part and found it by scanning items and looking for the signal. It was not long before this wire was found and I was able to receive UPC codes.

Scanning codes and building (Wunder)lists

When the scanner reads a barcode, it sends the ASCII representation of a UPC code to the attached Raspberry Pi Zero W. Brian used the free UPC Database to convert each code to the name of the corresponding grocery item. Next, he needed to add it to the Wunderlist shopping list that his wife uses for grocery shopping.

Raspberry Pi Barcode Scanner Wunderscan Brian Carrigan

Wunderlist provides an API token so users can incorporate list-making into their projects. With a little extra coding, Brian was able to convert the scanning of a pantry item’s barcode into a new addition to the family shopping list.

Curious as to how it all came together? You can find information on the project, including code and hardware configurations, on Brian’s blog. If you’ve built something similar, we’d love to see it in the comments below.

The post Scanning snacks to your Wunderlist shopping list with Wunderscan appeared first on Raspberry Pi.

Video: Overview of the Jrk G2 Motor Controllers with Feedback

via Pololu Blog

In our last blog post, we announced the release of our second generation of Jrk Motor Controllers with Feedback. If that announcement wasn’t enough to get you excited about the Jrks, here’s a short video to give you a taste of what the Jrks can do:

You totally want one now, right? Well lucky for you, our special introductory coupon is still valid. The first 100 customers to use coupon code JRKG2INTRO can get 40% off up to three units. (Click to add the coupon code to your cart.)

Friday Product Post: Pump Up the Jam!

via SparkFun: Commerce Blog

Well hello there, everyone, and welcome back to another fantastic Friday Product Post here at SparkFun Electronics. We have a pretty fun filled Friday in store for you with three aptly named audio boards for your choosing: a 1.5W stereo/mono amplifier with a built in potentiometer and two easy-to-use audio playback board. On top of these three new boards, we are also releasing a new 12 button keypad for whatever project you may need it for! Without further delay let’s take a closer look at all the new products we have for you this week!

With great power comes great responsibility… but that’s no fun! Just prank your friends with Smashmouth!

SparkFun Noisy Cricket Stereo Amplifier - 1.5W


You won’t need a series four de-atomizer with our rendition of the Noisy Cricket, just wire it up and crank up your tunes! The Noisy Cricket Stereo Amplifier, uses the LM4853 Boomer® IC which can be configured to output up to 1.5W of power in mono operation (4Ω load) or 300mW per channel in stereo operation (8Ω load). The amplifier comes with a dual-ganged pot with a built in switch to control power and adjust both left and right channel gain.


Noisy Cricket Stereo Amplifier - 1.5W Hookup Guide

April 26, 2018

A hookup guide for the Noisy Cricket Stereo Amplifier - 1.5W.

SparkFun Little Soundie Audio Player


The SparkFun Little Soundie is a fun and easy-to-use audio playback device breaking out the VS1000D audio codec IC allowing this little board the ability to decode OGG Vorbis and WAV type files. The Little Soundie makes adding sound effects to your project, prop, or costume easily with the built-in USB mass storage for your audio files and simple methods of triggering audio playback. Beyond playing back your chosen audio files, the Little Soundie is remarkably easy to set up, with just four simple steps: connect to your computer using a micro-USB cable, press the power/play button, format the disk when prompted, then just rag and drop your .ogg or .wav files!


Little Soundie Audio Player Hookup Guide

April 26, 2018

Add sound effects to your project, prop or costume with Little Soundie Audio Player.

SparkFun Papa Soundie Audio Player


The SparkFun Papa Soundie is the upgraded version of the Little Soundie with similar areas that allow you, the user, to interact with the board but with more customizable options. It still supports OGG Vorbis and WAV type files but with an SD card for sound storage and a built-in ATmega328P programmed with Arduino you’ll be adding custom sound effects to your project with less hardware and in a familiar programming environment.


Papa Soundie Audio Player Hookup Guide

April 26, 2018

Add sound effects to your project, prop or costume with Papa Soundie Audio Player.

Keypad - 12 Button


This is a basic 12 button keypad that has been designed for easy user input and functionality. The buttons are set up in a matrix format. This allows a microcontroller to ‘scan’ the 7 output pins to see which of the 12 buttons is being pressed.

Each of the keypad’s 12 buttons has been labeled 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, *, and # and has been formatted to into the same layout as a telephone keypad with each keypress resistance ranging between 10 and 150 Ohms.

Alright, folks, that’s all the new products we have for you this week. We hope you enjoyed the funny pranks in the video as well as giving all you audiophiles out there plenty of project ideas! As always, we can’t wait to see what you make with these products! Shoot us a tweet @sparkfun, or let us know on Instagram or Facebook. We’d love to see what projects you’ve made!

Thanks for stopping by. We’ll be back next week with even more fantastic new products!

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