Hacklet 36 – Oscilloscope Projects

Oscilloscopes are one of the most often used tools of the engineer, hacker, or maker. Voltmeters can do a lot, but when you really need to get a good look at a signal, a good scope is invaluable. This week’s hacklet is triggered by the rising slope of some of the best Oscilloscope projects on Hackaday.io!

rigol500We start with [DainBramage’s] recent project Stretching the Limits of a Rigol DS-1102E Scope. The new Rigol ds1054z may be getting all the press lately, but the older DS-1102E (100 MHz) model is still a very capable scope. [DainBramage] broke out his vintage Singer CSM-1 service monitor to generate frequencies all the way up to 500 MHz. The Rigol did admirably well, detecting a sine wave all the way up to 500 MHz. This is in part due to the scope’s 1 gigasample-per-second sampling rate. Once things got beyond the specified limit of 100 MHz though, the signal began to attenuate.  Not bad for pushing a low-end scope way beyond its limits!

 

cornel-scopeNext up is [Bruce Land] with his PIC32 oscilloscope. Microcontroller scope projects are nothing new, but one that runs at nearly 1 MHz sampling rate while generating NTSC composite video is nothing to sneeze at. [Bruce] pulled this off by using Direct Memory Access (DMA) to move the data from the ADC to memory, and to get the video data from memory to the I/O pins used to generate video. The video itself is created by a resistor tree DAC. All you need to make black and white video is three resistors and two I/O pins. [Bruce] says the entire scope cost about $4.00 us in parts!

scope-hand[Jacob Christ] mixed art and science with his chipKIT Oscilloscope Plotter. [Jacob] used a Microchip PIC32 based Fubarino to draw patterns on his scope. To do this the scope must be set to X-Y mode. [Jacob] paired his Fubarino with a MCP4902 Digital to Analog Converter (DAC). Using a dedicated DAC is a great way to do this. [Jacob’s] images are a testament to that, as they’re some of the cleanest “scope art” drawings we’ve seen. Much like [Bruce Land], [Jacob] used his project as the basis for a college class. In fact, the image to the left was created by one of his students!

Want more scope goodness? Check out our new Oscilloscope Projects List!

Hackaday.io Update!

Hackaday.io is getting new features every day. Our dev team has just rolled out a new gallery view. Just click on a project’s featured image, or the “View Gallery” button, and you will be taken to a gallery view of every image used in the project – including log images. YouTube videos will render in the gallery as well. It’s a great way to view a timeline of progress for some of the projects on hackaday.io. For a great example of this, check out OpenMV’s gallery.

In other Hackaday.io news, check out the Caption CERN Contest! Every week we put up a new image from CERN’s archives. The Hackaday.io user who comes up with the funniest caption wins a T-Shirt from The Hackaday Store!

Looks like we’ve hit the end of the trace for this Hacklet. Same hack time, same hack channel, bringing you the best of Hackaday.io!

Custom Case Made Entirely Out Of PCBs

So you’ve finished your project. You’ve got a wonderful circuit, a beautiful PCB, and everything works perfectly. You’re done right? Well, maybe not. Sure, a bare PCB might be fine for a dev board, but what if you have a LCD to mount, a knob that needs turning, and buttons that need pressing. Yeah, that potentiometer hanging off the board by a few wires isn’t so pretty, is it? So it’s time for a case. Yuck. We all hate modifying cases.

[Electrodacus] came up with a clever solution in the form of stacking PCBs to form a case. In his project, he actually has the circuitry spread across 3 PCBs, and uses surface mount connectors to connect them in a stack. Along the edges are specifically shaped PCBs to complete the enclosure. This technique could be used with only one PCB containing all the circuitry, and the others acting as the case sides and top.

In this solar battery management project, the base layer has most of the power circuitry. This layer uses an aluminum metal core PCB for heat dissipation. The center layer is home for the micro controller and supporting components. And the top layer is the “front panel” with capacitive touch buttons and a cut out for a LCD. The top layer silk screen contains the logo, button markings, and the pin out of all the connectors.

If you hate drilling and filling cases (as much as we do), this technique might be right for your next project.

[via EEVBlog Forums]

Control board for a Wi-Fi enabled thermostat

Controlling Central Heating Via Wi-Fi

If you’ve ever lived in a building with manually controlled central heating, you’ll probably understand [Martin]’s motivation for this hack. These heating systems often have old fashioned valves to control the radiator. No Nest support, no thermostat, just a knob you turn.

To solve this problem, [Martin] built a Wi-Fi enabled thermostat. This impressive build brings together a custom PCB based on the ESP8266 Wi-Fi microcontroller and a mobile-friendly web UI based on the Open Thermostat Scheduler. The project’s web server is fully self-contained on the ESP8266.

To replace that manual value, [Martin] used a thermoelectric actuator from a Swiss company called HERZ. This is driven by a relay, which is controlled by the ESP8266 microcontroller. Based on the schedule and the measured temperature, the actuator lets fluid flow through the radiator and heat the room.

As a bonus, the device supports NTP for getting the time, MQTT for publishing real-time data, and ThingSpeak for logging and graphing historic data. The source code and design files are available under a Creative Commons license.

Kitchen Timer

A Kitchen Timer Fit For MacGyver

Here’s a project that you don’t want to bring into an airport, ship through the mail, or probably even remove from your home. [ProjectGeek] has built himself a simple kitchen timer masquerading as a bomb. The build is actually pretty simple, but the end result is something that would look at home in a Hollywood action flick.

The timer circuit is built from four simple components. An 8051 microcontroller board is used as the primary controller and timer. The code is available on GitHub. This board is attached to a another board containing four momentary push buttons. These are used to program the timer and to stop the buzzing. Another board containing four 7-segment displays is used to show the remaining time on the timer. A simple piezo buzzer is used to actually alert you when the timer has run out. All of these components are connected with colorful jumper wires.

The physical part of this build is made from easily available components. Old newspapers are rolled up to form the “explosive” sticks. These are then covered in plain brown paper ordinarily used to cover text books. The rolls are bundled together and fixed with electrical tape. The electronics can then be attached to the base with some hot glue or double-sided tape.

The Best Way To Sport Your Tomatoes

Who eats tomatoes while they run in the first place? No one… and Japanese ketchup company, Kagome would like to change that.

Dole has been sponsoring the Japan Marathon for years, supplying runners with ready to eat bananas to gnosh on-the-go for a quick boost of nutrients. Part of their advertising campaign this year is a Wearable-edible Banana that runners can eat hands free. Out of good humor and a desire to one-up the absurdity level, Kagome worked with known Japanese group, Maywa Denki to create the Tomatan, a smiling contraption that mounts on a runner’s shoulders and delivers tomatoes from a hopper directly into their face… as a reminder that though Japan could be eating wearable bananas, they could just as easily eat mechanically dispensed tomatoes instead.

Why is this awesome? When we’re talking about silliness and commercialism in Japan, the aforementioned Maywa Denki seems to always surface like a nonsense wielding genie. If you haven’t heard the name, this company is actually the identity of an artist group. They have a reputation for inventing mechanical gizmos that are humorously ridiculous, and then marketing them as serious products part of the Maywa Denki brand. The sixteen-pound piggy-back tomato feeder meant to help improve a runner’s stamina is just one example of their many “nonsense machines”.

When we bring the things we create to market, they are usually presented to the world as products of some sort. Maywa Denki bends this common concept of the product to create an identity around their works of art. Because why not solve an imaginary problem that doesn’t really need a solution?

Makes you wonder what kind of obnoxious contraption you’d build to wear in a crowd, huh?:

https://www.youtube.com/watch?v=oUXj5bZcNaY

Dole Japan’s Wearable Banana propaganda:

https://www.youtube.com/watch?v=qIa_Ik2QRh0#t=22

Ro-Bow, The Violin Playing Robot

There are robots that will vacuum your house, mow your lawn, and keep their unblinking electronic eyes on you at all times while hovering hundreds of feet in the air. How about a robot that plays a violin? That’s what [Seth Goldstein] built. He calls it a ‘kinetic sculpture’, but there more than enough electronics and mechatronics to keep even the most discerning tinkerer interested.

There are three main parts of [Seth]’s violin-playing kinetic sculpture. The first is a bow carriage that draws the bow across the strings using an electromagnet to press the bow against the strings. The individual strings are fingered with four rubber disks, and a tilting mechanism rotates the violin so the desired string is always underneath the bow and mechanical fingers.

As far as software goes, the Ro-Bow transforms MIDI files into robotic mechanization that make the violin sing. From what we can tell, it’s not quite as good as a human player; only one string at a time can be played. It is, however, great at what it does and is an amazing mechanical sculpture.

Video Below.

Continue reading “Ro-Bow, The Violin Playing Robot”

Volvo Phone Holder

DIY IPhone Mount For A Volvo

[Seandavid010] recently purchased a 2004 Volvo. He really liked the car except for the fact that it was missing some more modern features. He didn’t come stock with any navigation system or Bluetooth capabilities. After adding Bluetooth functionality to the stock stereo himself, he realized he would need a secure location to place his iPhone. This would allow him to control the stereo or use the navigation functions with ease. He ended up building a custom iPhone mount in just a single afternoon.

The key to this project is that the Volvo has an empty pocket on the left side of the stereo. It’s an oddly shaped vertical pocket that doesn’t seem to have any real use. [Seandavid010] decided this would be the perfect place to mount his phone. The only problem was that he didn’t want to make any permanent changes to his car. This meant no drilling into the dash and no gluing.

[Seandavid010] started by lining the pocket with blue masking tape. He then added an additional lining of plastic wrap. All of this was to protect the dashboard from what was to come next. He filled about half of the pocket with epoxy putty. We’ve seen this stuff used before in a similar project. He left a small opening in the middle with a thick washer mounted perpendicular to the ground. The washer would provide a place for an off-the-shelf iPhone holder to mount onto. [Seandavid010] also placed a flat, wooden paint stirrer underneath the putty. This created a pocket that would allow him to route cables and adapters underneath this new mount.

After letting the epoxy putty cure for an hour, he removed the block from the pocket. The stick was then removed, and any gaps were filled in with putty. The whole block was trimmed and smooth down for a more streamlined look. Finally, it was painted over with some flat black spray paint to match the color of the dashboard. An aftermarket iPhone holder allows [Seandavid010] to mount his cell phone to this new bracket. The cell phone holder allows him to rotate the phone into portrait or landscape mode, and even is adjustable to accommodate different sized phones.