I’m a big fan of the Playstation video game consoles, so when I learned about the PS2X library by Bill Porter, I had to try it out. PS2X makes it easy to interface Arduino microcontrollers with Playstation 2 controllers. After wiring everything up and testing it with the sample program, I set out to find something more interesting to do with it. The result is a stepper motor that is controlled by the Sony controller. Here’s a video of it in action:
This was a random find on Ebay, just something I came across while looking for something else. I really liked the look of it, and I needed something that could measure large currents anyways, so I bought it. I have a Sparkfun digital multimeter, which is a steal at $15 and serves most of my needs as a hobbyist, but it’s best used for low current measurements, under 200ma. It can do up to 10 amps, but only for 10 seconds. It’s a useful feature, but sometimes I want to watch a circuit’s current for an extended period of time. I don’t want to buy an expensive DMM when the Sparkfun unit serves 98% of my needs, so an analog ammeter seemed like a good compromise. It may not be as accurate as a DMM, but it’s good enough for my needs.
I don’t know much about the meter, other than it was made by a company called Stansi located in Chicago, and it has three ranges of measurement: 0-1.5 amps, 0-3 amps and 0-30 amps. After receiving the meter, I tried it out, and found that the measurements it was giving all seemed to be significantly off. I was disappointed; I liked the look of it, but I didn’t buy it to be an antique, I bought it to actually use! I noticed that the connections on the underside of the meter were all corroded quite a bit, so I took all of the connections apart, cleaned all of the posts, washers, nuts and other bits and pieces with steel wool, and put everything back together. After testing it some more, it seems that all it needed was a good cleaning, the measurements are all very close now when compared to the DMM. Success!
If you’re hobbyist like me, and need to measure large currents but don’t want to spend the money on an expensive DMM that you don’t really need, then an analog ammeter may be the solution. A digital display certainly has significant advantages in terms of speed an accuracy, but if you buy a large meter, it should be easy to get a “close enough” measurement. In the photo to the left you can see the Stansi meter connected to a BigClive.com RGB controller, and it’s clear that it’s pulling approximately 320ma of current. It may not be as quick or accurate as a DMM, but there’s something about watching that needle bounce around that an LCD display can’t replicate, and for $20 and an hour of my time, it’s a good value. I expect to get lots of use out of this meter.
At some point while researching microcontroller projects, I came across several people who had used Arduinos and PICs to drive analog panel meters so they would display computer stats such as CPU load, memory usage, etc. It immediately struck me as something I just had to do. Here it is. My PC meter uses an Arduino microcontroller and receives the stats from a .NET Framework application I wrote in C#.Net. It’s housed in a plastic enclosure and looks quite professional IMHO. It was a fun project, and something I think most any computer/electronics geek would enjoy. I love mine, and I look forward to building more.
Here it is in action:
Read on for details on the parts and tools I used, some info on the process of building the device (and the problems I ran into) and links to download the source code and meter templates.
This past weekend marked the 14th annual Garage Sale Bonanza, held at the Saybrook Plaza in Saybrook Township, Ohio. It’s a large event, including just about everything you’d typically find at a garage sale except clothing. All of the items sold are donated to the event and it is staffed entirely by volunteers. Proceeds from the event benefit a variety of local non-profit organizations, including an animal shelter, senior center, clothes closet, transitional housing, cancer support group and several other worthy organizations. I volunteer at the event each year, organizing, testing and repairing computer equipment and misc. electronics, and every year I also shop the event. It’s a great place to find parts, tools and other bits and pieces for making things.
Oftentimes, I find myself going to my parents’ house or a friend’s place to build or repair something, and I have nothing to put my larger tools in. As a result, my drill, saw, clamps and other large items end up either laying on the floor of my truck or stuffed into whatever cardboard box I found laying around. If I had a large, sturdy box to throw this stuff in, it would make these trips much more convenient and I would spend less time loading and unloading my tools and more time working. So when I saw Len Cullum’s Japanese Toolbox project in MAKE 34, I knew I had found my solution.
I recently reviewed the Color Night Joule Thief by The LED Artist, and tonight I built the original Night Joule Thief. It works just like the color version, except that it uses two white LEDs instead of a single color-changing LED, and has slightly fewer components. Unlike the color version, I didn’t run into any problem with the PCB layout; everything fit with no risk of any short circuits. Assembly is easy and well-suited for a beginner.
Light output is very good using a fairly new battery. I tried it in my bedroom and it provides enough light to keep me from stubbing my toes on the bed posts after dark. With that said though, I wish the output was spread out more, it’s very narrowly focused. This could be adjusted to some degree by soldering the LEDs so they point at different angles. Another possible solution is using LEDs with a wider output beam. I purchased two kits, so I may try doing something like this with the other. Other possible modifications which are discussed on the related Instructables page include using a switch instead of a photoresistor to turn the LEDs on and off, and using alternative battery clips to allow for C, D and other size 1.5v batteries.
Overall, this is an excellent kit, perfect for beginning electronics enthusiasts learning to solder as well as experienced hobbyists looking for a simple circuit to build that offers some room for customization. It’s available for under $11 from The LED Artist.
While testing my recently acquired Piranha LEDs, I noticed quite by accident that the output from the breadboarded circuit created some interesting effects when used to cast shadows against a plain background. The edges of the shadows show the red, blue and green (and mixed) colors due to their coming in from slightly different positions and angles. It’s a fun effect, but there isn’t much room for creativity as my test circuit only had 6 LEDs (2 of each color) grouped closely together. Something more interesting and dramatic could be achieved using larger light sources positioned further apart, which would allow control over where the different colors fall and how much they overlap. It’s something I may pursue in the future when I have more lights built. Until then, here’s a couple photos I snapped and a video I quickly put together using my test circuit.
The first photo is (quite obviously) my hand and the second is a failed amplifier circuit I had laying around.
And a video, which came out creepier than I had intended. A friend described it as “Dr. Frankenstein visits Studio 54!”
I’m planning an LED floodlight project that will use a lot of square 4-pin LEDs, aka SuperFlux or “Piranha” LEDs. I hadn’t had a chance to use these type of LEDs until now, so after receiving my order this week I immediately went to work on trying them out. This won’t be a very technical review, just a quick look at the specs and my experience with testing the LEDs and what I thought of them.
I recently stumbled upon Akimitsu Sadoi’s website, The LED Artist. Akimitsu describes himself as a Brooklyn, NY based electronic artist with the motto “Art and Technology are Friends”. He designs and builds LED Art projects and offers a variety of kits for sale through his online store. I’m a sucker for anything that lights up, so it didn’t take me long to find several kits I wanted to purchase and build. I can’t afford to buy every kit I want on there, but I did pick up a couple, the smaller (and cheaper) of which is the Colour Night Joule Thief.
The cMoy Headphone Amplifier is a popular, well-documented DIY project, which makes it great for beginners to take on. That’s exactly the reason I chose to do it. I followed the instructions and suggestions from the TangentSoft cMoy Tutorial written by Warren Young, and it came out great, especially for my first attempt at building a headphone amplifier.
I won’t get into how I built mine (the tutorial at TagentSoft is where you should go for that) but read on if you’re interested in seeing what parts I used and some of the problems I ran into.