Happiness is a pile of freshly clipped component leads

It’s amazing how working with electronics can bring so much fulfillment, simultaneously with so much aggravation. There was no SMMR yesterday because I was hard at work on my latest project, a function generator.


Whenever I get to solder together a circuit board, I go into soldering zen mode. Soldering a few joints, blowing away the smoke, checking my work, and clipping the leads short. That’s my favorite part. Clipping off the excess leads is so satisfying, like putting my stamp of approval on the board. Of course the moment of truth comes later, when you actually turn the thing on.

I have been wanting to put together another amplifier, but I have been lacking in decent test equipment, namely a clean signal source for testing said amplifier, so I decided to make one. Except I wanted it to be small, which means no perfboard. I didn’t have a laser printer, so I rescued one bound for the scrap pile at work, got it to print (intermittently) and got to work. Here’s the result:

Fun fact: printing your toner transfer pattern on a glossy page of Nuts & Volts produces superior toner transfer PCBs.

Amazingly, when I got everything wired up, and flipped on the power, the thing worked on the first try. I can’t speak for anyone else, but for me, powering up a brand new circuit generally results in a whole lot of nothing, followed by six hours of tracing signals through a board and swearing loudly, so I was pretty ecstatic. However…

I am getting these weird glitches at the peaks of the waveform. I’m not sure where they are coming from, but this is my current source of the aggravation I mentioned earlier. I have spent most of today trying to get rid of them, but they are very resilient and are laughing at my feeble attempts at banishing them.

Overall, I am still very happy with my new function generator. It works great for what I need, but it still needs a little bit of polishing before it is ready to publish as a project. Check back soon for deets on making your very own ultra-configurable, low(ish) distortion, 10Hz to (almost) 100kHz function generator.

Someone in Cupertino is listening

Now that I have five whole Facebook fans (Hey, Rachael!), I’m kind of a big deal in the tech-blogosphere. This is proven by someone at 1 Infinite Loop revealing that Apple will be   shrinking the bezels on the next generation of the iPad, just like I said they should.

I know the target market for this blog could be counted pretty easily be any barefoot electronics hobbyist, and that my writing and subject matter can be as random as my last metaphor, but thanks for reading.

Sweet, sweet silence

Power went out this morning. It was beautiful. I love it when the power goes out. I don’t love stumbling around in the dark, or trying to shave by candlelight, or having the loudifier datacenter (my house) get cut off from the interwebs, but I like hot cocoa, and snuggling down into entirely too many layers of blankets. But my favorite part of the power going out is the silence.

We spend so much of our lives trying to get everything to sound just right, from ringtones and notifications, to the perfect live studio mix, to the rumble of an engine, to the tone of a guitar effect, and the noise floor of our daily lives is raised to the point that we don’t understand silence and we unknowingly settle for quiet. When the power goes out, there might be a little wind, or dogs barking, but the furnace stops blowing, hard drives spin down, and even the whine emitted by wall warts, which was previously masked by innumerable clicks, whirs, and buzzes of our modern life, is cut off. Your subconscious stops resonating with the 60 Hz hum being broadcast by every appliance in the kitchen.

I had a band teacher in seventh grade, Mr Bliss. He was a genius, in a manic sort of way. He talked about silence as a tool for the musician, and we would drill on maintaining complete silence before and after a song, or when a passage called for a full-band rest. He would say “Music is a collection of sounds and silences, and sometimes it is the silence that makes the sound so profound”. He would demand silence from the audience during performances, and we sounded better because of it.

In electronics, audio, digital, or otherwise, there is always noise, riding on the signal, sneaking in from the power supply. We use error checking, and hysteresis, and shielding, and differential signal pairs, and creative filtering, but it is always there. We define “acceptable” noise levels, and proudly proclaim in dB just how good we are at eliminating noise, but at the end of the day, we still have to accept it. Part 15 of the FCC says that we legally have to accept it, and physics says that we can’t just wish it away. 

But when the power goes out, we can get pretty close to eliminating noise. Those brief spans of time give us some contrast in the soundscape of our lives, and make the noises that we want to hear a little more profound.

So this morning I just dozed a little bit, enjoying the silence.