Stylophone 5 – Modernizing The Best Of The 1968 Hardware

We love looking in on [Simon Inns’] projects, and this must be one of his very best. This is the fifth version of his MIDI-capable stylophone. The gist of the control system is that a conductive keyboard (made of a tinned PCB) is played by making a connection with the tip of a wired stylus — hence the name. The idea comes from the original 1968 Dubreq Stylophone hardware, but [Simon’s] not just using the idea. He has his own working original and used it to reverse engineer the circuit design.

When it first came out, the Stylophone had three flavors for Bass, Standard, and Treble audio ranges. They differed only in the choices of passive components used in the circuit. [Simon] built the variations into his design so that they are selectable on one unit. This most recent version connects via USB, allowing you to control MIDI software. But unlike his first four iterations, this also offers MIDI-In capabilities. This makes it possible to control tuning, vibrato, and to drive the Stylophone circuitry from the computer interface. Get a good look at that, and a nostalgic Portal moment, by watching the clip after the break.

If you’re looking for an easier build, you might try this analog standalone version of the Stylophone.

Continue reading “Stylophone 5 – Modernizing The Best Of The 1968 Hardware”

Audio Output Selection Courtesy Of The Internet

[Peter] was tired of crawling behind his desktop computer to switch between headphones and speakers. We feel his pain, as the headphone port on our computer speakers has its own demonic hum rendering the jack useless to us. His solution was to build this output selector board, then control it via the network.

A relay is responsible for routing the single input to one of two outputs. One output is wired to the normally closed pin on the relay, the other to the normally open pin. The important thing here is to make sure you have a separate audio ground so as not to pick up noise from the rest of the hardware.

What you see above is only the switching circuitry. This is where [Peter] went a little overboard, using an Arduino along with an Ethernet shield to drive the relay via a transistor. For this particular application there must be an easier way. But if you’re working on home automation from your smart phone, this might be just the thing to make your audio setup browser-controlled.

[via Build Lounge]

ColorHug: A Reasonably-priced, Completely Open Color Calibration Tool

colorhug-opensource-color-calibrator

[Richard] wanted to create a color profile for his computer monitor, but he wasn’t thrilled with the existing color calibration offerings he found for sale. Color calibration tools can be somewhat costly, but even more troubling to [Richard] was the fact that they are all closed source. Closed hardware and closed software can be a drag, especially when manufacturers drop support for a product, so he set off to design his own open-source monitor calibration tool.

Once his ColorHug sensor is placed against a monitor, it begins sampling colors from the screen, creating an ICC color profile from the data it gathers. The sensor is a Linux-only tool at the moment, but he has created a live CD from which a color profile can be created, then subsequently used in Windows or OSX.

While ColorHug doesn’t sport all the features of its commercial competitors, its color sampling rate is second to none, and since the software is open, anyone is free to implement any sort of functionality they wish.

[Richard] is currently selling finished ColorHug modules to anyone interested in giving them a test drive, but you can always build your own from the plans found at ColorHug’s Github repository.

[via Adafruit blog]

Solder Reflow Toaster Oven

[Sebastian] needed a small solder oven so he bought himself a small toaster oven (Spanish, Google Translate). It’s not the kind of thing we’d make our breakfast in now, but for soldering it’s a very nice oven.

After a little bit of research on Google, [Sebastian] discovered that the best technique when dealing with reflow ovens and solder paste is following a specific temperature curve. Ideally, Tin/Lead solder needs to preheat from room temperature to 150 degrees C, then level off so the flux can activate. After that, a quick jaunt above 183 degrees C makes the solder flow. To get his toaster working optimally, [Sebastian] stuck a thermistor in the toaster and measured the temperature profiles of different ‘modes.’

The correct temperature curve was calculated using different heater elements and [Sebastian] was off to the races. He did have a few problems on his first few boards – solder bridging, mostly – but that’s not the fault of the oven. An LCD display (translate) was added recently so accurate real-time temperature monitoring is available.

The Origin Of The Arduino

If you ever wondered how the Arduino came into being, check out [IEEE Spectrum’s] article entitled “The Making of Arduino.” From it’s humble origins in Northern Italy, the Arduino, as shown by a large number of projects featured at [HAD], has become the go-to processor for DIY processing power. It’s cost (around $30) and ease-of-use are some of the biggest factors allowing it to become such a huge success.

One thing that interests many people about the Arduino is that it is totally open source, licensed under the Creative Commons License.  This was quite innovative in itself since the CCL was generally applied to works of art like music and writing.  Despite the fact that [Banzi] and his team decided to literally give the design away, 0ver 250,000 of these boards have been sold worldwide not including their many clones.

If you’re wondering how it got the name “Arduino”, it’s named after a bar named “Bar Di Re Arduino” in the Northern Italian town of Ivrea.

Build Your Own Stereolithographic 3D Printer

[Andy’s] 3D printer build uses lasers to create objects from goo. The Stereolithographic process uses resin that is cured by UV light to create the finished product. A single laser mounted to a CNC gantry is able to precisely target a point on the surface of the resin to begin the printing process. As the layers are built up, the stage, which is mounted on the Z axis, slowly sinks into the resin vat. So basically you’re printing from the bottom up but the laser never moves up or down. There’s a time-compressed video of an object being printed embedded after the break. It illustrates the process better than we can describe it.

We think [Andy] really went all out with his write-up of the build process. The quality he achieves in his prints is quite excellent, but you must consider the cost versus an extrusion-based 3D printer. One liter of the UV resin he prints from can cost over $200.

If this sounds familiar it’s because we got a sneak peek at it back when we looked in on his Delta robot work.

Continue reading “Build Your Own Stereolithographic 3D Printer”

Nixie Clock Exhibits Well Fabricated Metal Bezel

[Matt Evans] achieves a total win with his Nixie clock. Not only does he have the benefit of the retro display hardware, but he really catches our eye with the enclosure he built for it.

The project had its genesis when he came across a set of the Nixie Tubes in a surplus store. This was back in 2007, and with parts in hand he built the high-voltage driver circuit and a control board. The thing kept time, but was housed in a temporary case that was a bit rough looking. There it sat, waiting to become the focus of his attention once again.

When it did finally come time to build a proper case [Matt] started with a small sheet of recycled copper. He made the cutouts and bends by hand. He mentions that it’s a little uneven; maybe, but we don’t think it detracts from the design. Some black screen (like would be used on a porch door) covers the openings, giving texture and contrast to the facade.

We love the look, and the ATmega48 with a clock crystal for the RTC functions should make this a reliable time source.