Make Your Own Arduino Header Pins

There are two kinds of people in the world (and, no, this isn’t a binary joke). People who love the Arduino, and people who hate it. If you’ve ever tried to use a standard prototype board to mount on an Arduino, you’ll know what kind of person you are. When you notice the pins aren’t on 0.1 inch centers, you might think, “What the heck were those idiots thinking!” Or, you might say, “How clever! This way the connectors are keyed to prevent mistakes.” From your choice of statement, we can deduce your feelings on the subject.

[Rssalnero] clearly said something different. We weren’t there, but we suspect it was: “Gee. I should 3D print a jig to bend headers to fit.” Actually, he apparently tried to do it by hand (we’ve tried it, too). The results are not usually very good.

He created two simple 3D printed jigs that let you bend an 8-pin header. The first jig bends the correct offset and the second helps you straighten out the ends again. You can see the result in the picture above.

Continue reading “Make Your Own Arduino Header Pins”

Hackaday Prize Entry: Reverse Engineering Blood Glucose Monitors

Blood glucose monitors are pretty ubiquitous today. For most people with diabetes, these cheap and reliable sensors are their primary means of managing their blood sugar. But what is the enterprising diabetic hacker to do if he wakes up and realizes, with horror, that a primary aspect of his daily routine doesn’t involve an Arduino?

Rather than succumb to an Arduino-less reality, he can hopefully use the shield [M. Bindhammer] is working on to take his glucose measurement into his own hands.

[Bindhammer]’s initial work is based around the popular one-touch brand of strips. These are the cheapest, use very little blood, and the included needle is not as bad as it could be. His first challenge was just getting the connector for the strips. Naturally he could cannibalize a monitor from the pharmacy, but for someone making a shield that needs a supply line, this isn’t the best option. Surprisingly, the connectors used aren’t patented, so the companies are instead just more rigorous about who they sell them to. After a bit of work, he managed to find a source.

The next challenge is reverse engineering the actual algorithm used by the commercial sensor. It’s challenging. A simple mixture of water and glucose, for example, made the sensor throw an error. He’ll get it eventually, though, making this a great entry for the Hackaday Prize.

The HackadayPrize2016 is Sponsored by:

Teensy Gets A Prop Shield

God of microcontrollers and king of electrons [Paul Stoffregen] is famous for his Teensy microcontroller dev boards, and for good reason. If you have a project that does more than blink a few pins, but doesn’t need to run a full Linux build, any one of the Teensy dev boards are a great option. As a dev board, [Paul] has released a few ‘shields’ that add various functionality – for example the audio adapter board that is able to play CD quality audio and perform DSP and FFT operations. Now, [Paul] has launched a new shield designed for interactive light and sound effects on art installations and for the rest of the crew at Burning Man. It’s called the Prop Shield, and adds more sensors, audio amps, and blinkies than a Teensy has ever had.

The Teensy Prop shield is equipped with 10DOF motion sensors, including a FXOS8700 accelerometer/magnetometer, a FXAS21002 gyroscope, and an MPL3115 altimeter and temperature sensor. A two Watt LM48310 audio amplifier can drive 4 or 8 ohm speakers, and 8 Megabytes of Flash memory can hold all the data for audio or a very long string of APA102 individually addressable LEDs.

The combination of motion sensors, audio amplifiers, and LED drivers may seem like an odd combination, but this is a shield for very odd projects. Stage effect, wearables, and handheld props become very easy with this board, and haunted houses are about to get really cool. With the on-board Flash, this board makes for a very capable data logger, and although the altitude sensor only reads pressure up to about 40,000 feet, this could be a very handy board for high altitude balloons.

The Prop Shield is available now in [Paul]’s shop. There are two versions, one ‘wit’ the motion sensors for $19.50, and the other ‘witout’ motion sensors for $8.40. The distinction is based on the Philly Cheesesteak protocol.

For the last few weeks, [Paul] has put the prop shield in the hands of a few dozen beta testers. Their impressions are in a forum thread, and like all of [Paul]’s projects, the response has been very good.

Tiny Raspberry Pi Shield for High-Quality RF Signals

Among its many tricks, the Raspberry Pi is capable of putting clock signals signal out on its GPIO pins, and that turns out to be just the thing for synthesizing RF signals in the amateur radio bands. What [Zoltan] realized, though, is that the resulting signals are pretty dirty, so he came up with a clever Pi shield for RF signal conditioning that turns a Pi into a quality low-power transmitter.

[Zoltan] stuffed a bandpass filter for broadband noise, a low-pass filter for harmonics, and a power amplifier to beef up the signal a bit into a tiny shield that is cleverly engineered to fit any version of the Pi. Even with the power amplifier, the resulting transmitter is still squarely in the realm of QRP, and the shield is optimized for use as a WSPR beacon on the 20-meter band. But there’s plenty of Pi software available to let hams try other modes, including CW, FM, SSB, and even SSTV, and other signal conditioning hardware for different bands.

Yes, these are commercially available products, but even if you’re not in the market for a shield like this, or if you want to roll your own, there’s a lot to learn from [Zoltan]’s presentation at the 2015 TAPR Digital Communications Conference (long video below). He discusses the difficulties encountered getting a low-profile shield to be compatible with every version of the Pi, and the design constraints that led to the decision to use SMT components.

Continue reading “Tiny Raspberry Pi Shield for High-Quality RF Signals”

Finally, a Modern Theremin

Ever wanted to own your own Theremin but couldn’t justify dropping hundreds of dollars on one? Now you can build your own, or buy it for a quintuplet of Hamiltons. The Open.Theremin.UNO project has built up antenna-based oscillator control around the ubiquitous Arduino Uno board.

So what’s the Arduino in there for? This is a digital Theremin, but check out the video below and you’ll agree that it sounds amazing and has excellent response. The aluminum antennas used for volume and pitch are attached to the top portion of the shield but it sounds like they’re not included in the kit. Don’t fret, you can use a variety of materials for this purpose. On the bottom you need to connect a speaker cable, and also a ground wire if that cable’s not grounded.

As the name implies, this is Open Hardware and we’re quite happy with the documentation on their site and the BOM (found on the GitHub repo). This design was shown off back in 2013 hiding in a pack of cigarettes. If you don’t want to build your own they’re selling kits on their site for 48 Euro delivered, or on Tindie for $55.

Okay, we’ve screwed this up so many times that we’re going to try to get it right here: the Theremin was not heard in the opening of Star Trek the original series, or in the opening of Doctor Who. It wasn’t featured in “Good Vibrations” either. As far as we can tell, it’s not used for anything in pop culture at all… but recognizing the sound and knowing what one is remains core geek knowledge.

If you want a Theremin to play using your entire body you need the Theremin Terpsitone.

Continue reading “Finally, a Modern Theremin”

HamShield Puts Your Arduino On The Radio

Anybody can grab a USB TV tuner card and start monitoring the airwaves, but to get into the real meat of radio you’ll need your amateur radio license. Once you have that, the bandwidth really opens up… if you can afford the equipment. However, [spaceneedle] and friends have dramatically lowered the costs while increasing the possibilities of owning a radio by creating this ham radio shield for the Arduino.

The HamShield, is a versatile shield for any standard Arduino that allows it to function like an off-the-shelf radio would, but with a virtually unlimited number of functions. Anything that could be imagined can be programmed into the Arduino for use over the air, including voice and packet applications. The project’s sandbox already includes things like setting up mesh networks, communicating over APRS, setting up repeaters or beacons, monitoring weather stations, and a whole host of other ham radio applications.

HamShield operates on a wide range of frequencies and only uses a 250 mW amplifier. The power draw is small enough that the HamShield team operated it from a small solar panel, making it ideal for people in remote areas. The project is currently gathering funding and has surpassed their goal on Kickstarter, branding itself appropriately as the swiss army of amateur radio. The transceiver seems to be very robust, meaning that the only thing standing in the way of using this tool is simply writing the Arduino code for whatever project you want to do, whether that’s as a police scanner or even just a frequency counter. And if you want to follow along on, the project can be found here.

Continue reading “HamShield Puts Your Arduino On The Radio”

Bread Online is a Bread Maker for the Internet of Things

An engineering student at the University of Western Macedonia has just added another appliance to the ever-growing list of Internet enabled things. [Panagiotis] decided to modify an off-the-shelf bread maker to enable remote control via the Internet.

[Panagiotis] had to remove pretty much all of the original control circuitry for this device. The original controller was replaced with an Arduino Uno R3 and an Ethernet shield. The temperature sensor also needed to be replaced, since [Panagiotis] could not find any official documentation describing the specifications of the original. Luckily, the heating element and mixer motor were able to be re-used.

A few holes were drilled into the case to make room for the Ethernet connector as well as a USB connector. Two relays were used to allow the Arduino to switch the heating element and mixer motor on and off. The front panel of the bread maker came with a simple LCD screen and a few control buttons. Rather than let those go to waste, they were also wired into the Arduino.

The Arduino bread maker can be controlled via a web site that runs on a separate server. The website is coded with PHP and runs on Apache. It has a simple interface that allows the user to specify several settings including how much bread is being cooked as well as the desired darkness of the bread. The user can then schedule the bread maker to start. Bread Online also comes with an “offline” mode so that it can be used locally without the need for a computer or web browser. Be sure to check out the video demonstration below. Continue reading “Bread Online is a Bread Maker for the Internet of Things”