Here’s a no-PCB Arduino that doesn’t obscure the DIP footprint of the AVR chip. It’s built on an ATmega88 chip, and includes a programming header, reset button, a couple of filtering caps, and an LED. This is modeled after the Lilypad hardware, and fits nicely on top of the plastic case of the microcontroller, allowing it to be used in a breadboard or DIP socket. You can see a walk through of the components in the clip after the break.
We don’t really need most of the components on top of the chip (especially the status LED on the SCK line), but there are several things that we like about this. First off, the programming header is extremely nice. We could see this coming in handy for prototyping where you don’t want to add a header to your final design. Just use a chip socket, and this chip while you’re developing firmware. Once everything is dialed in, program a naked chip and swap the two. The same goes for the reset button, which is nice when working on firmware but may not be necessary in your final design.
This is quite an old project, and we’ve actually seen a successor to it. This is Rev. 2 and we looked in on Rev. 7 back in March. That one is a full Arduino, but the circuit board has no substrate.
Continue reading “Dead-bug Arduino is still breadboard ready”
The most recent installment of [Dino Segovis’] Hack a Week covers the construction of a simple NPN transistor audio preamp. Some time ago, he built a small audio amplifier using an LM386 which worked well, but didn’t quite get his music as loud as he would like it. He decided to build a preamp to complement his amplifier, and demonstrates how you too can build one with just a small handful of components.
As the name probably suggests, the cornerstone of this amplifier is an NPN transistor. He explains that a forward bias is applied to the base-emitter junction, which results in the transistor operating halfway between its cut-off and saturation regions. Both halves of the input audio signal are superimposed on this bias voltage, resulting in a decent amount of gain across both channels from a relatively small package.
The preamp isn’t going to win any awards among audiophiles, but it is definitely a great beginner project. Its a novel way of demonstrating how transistors work, while producing a useful takeaway piece of audio equipment at the same time.
Continue reading to see a video showing just how big an effect [Dino’s] NPN preamp had on his music.
Continue reading “Quick and easy audio preamp”
Everyones favorite site, Instructables.com, has announced a big move. They have joined Autodesk along with the same team that is doing Autodesk 123D,
Autodesk is a great cultural fit for Instructables. They make tools for creative people: they’re the world leader in 3D design, engineering, and entertainment software. Even if you don’t recognize the name Autodesk, their software has powered the movies you watch, and designed the cars you drive and the buildings you work in. Instructables will be the community arm of the same team that makes 123D, SketchBook, Homestyler, and Pixlr, which will help provide creative tools, inspiration, and services for all types of creative people. Here’s Carl Bass, Autodesk’s CEO, talking more about his vision for the future of DIY.
Sofar the overall reaction on the site thread is tame, but many comments lean to skeptical, though typical with any transition to “The man” as one commenter called them.
Meanwhile MAKE has posted a in depth article “Autodesk Acquires Instructables: What It Means for Makers” in their usual (long) format. What’s your thoughts?
“Wednesday, I was arrested and sent to jail,” is what your blog might say if you decide to try and duplicate this project. You may, however, be fortunate to be still writing your blog, as ATTEMPTING TO BUILD YOUR OWN REACTOR can be quite dangerous. That’s what [Richard] did using household items such as clock fingers for Radium, and smoke detectors for Americium. After the radioactive elements were separated from their household “containers” and melted down, they created a small explosion on his stove.
This attempted experiment is based on one that was done by [David Hahn], AKA, “The Nuclear Boyscout”, in order to obtain his nuclear energy badge. For what it’s worth, [David] did attain the rank of Eagle Scout, however, he turned his parent’s house into a Superfund EPA cleanup site in the process.
The video after the break describes the process of making a reactor from household materials. This video may be entertaining, but duplicating it is not recommended (and would be somewhat expensive). Continue reading “The DIY Nuclear Reactor”
[Alex Busman]‘s first foray in iOS programming looks like a pretty useful tool. He came up with Ohm Sense, an iPhone app that will take a picture of a resistor and calculate the value based on the color bands. It’s a great tool that we wish we had when we were starting out. At 99 cents, the app is also much cheaper than the emotional cost of our relationship with Violet.
Continue reading “Ohm Sense makes sense of resistor color bands”