Category Archives: Engineering

You don’t know jack about optical audio

Photo by Hustvedt, via Wikimedia Commons

If the back of your entertainment system looks like a cross between mission control and a 1960s Manhattan switchboard, you could probably use a little help separating your composite from your component video. In this article, I’ll explain the oxymoronic mystery that is optical audio, with stops along the way to explore the evolution of inputs, outputs, standards and jacks that led to it. I’ll also tell you how this fiberoptic system stacks up against HDMI.

What is Optical Audio?

Funk with me if you want to live

Is the world clamoring for a dancing robot-speaker? Perhaps not. Then again, I probably said the same thing about Big Mouth Billy Bass, Let’s Rock Elmo or Furby. Heck, something has to be the toy that dominates Christmas.

So, read on. After all, it’s Bieber-certified.

How the mRobo Ultra Bass Works

Starlight, star bright, first shot I snap tonight

Infrared photo of Webster's Falls
Photo: Marcus Qwertyus/Wiki Commons

Photography is all about light; it’s right there in the name: photo (“light”) + graph (“means of recording”). So how do you shoot in the gloom between the golden hours? Well, you have a few options. You can pop in a flashbulb. You can try your hand at painting with light – that is, fiddling with f-stops and shutter speeds to let more light in over a longer period. Unfortunately, flashbulbs tend to wash out photos, and setting up longer exposures tends to limit your photographic freedom.

Night-vision cameras and attachments get around these problems, either by amplifying existing light or working with a different kind of ambient “light” – aka infrared radiation, either from body heat (thermal IR) or from an active IR illuminator attached to the camera. Today, infrared and ultraviolet cameras also make useful tools for inspections and field work. But how do they work, and what is their history?

How Night-vision Cameras Work

Lave Ferrous: The secret lives of magnetic soaps

There’s an old run of Peanuts in which Charlie Brown is repeatedly confronted by girls skipping “hi-fi” jump ropes or wearing “hi-fi” bracelets. Each strip ends with Charlie Brown loudly questioning how such an object can be hi-fi, but of course we know the answer: marketing.

Magnetic soap has that sort of ring to it, too. But there are actually good reasons for making surfactants – the group of surface-tension reducing substances to which soap belongs – stick to magnets. Imagine cleaning up an environmental disaster like the Deepwater Horizon oil spill without leaving any of your cleanup materials behind, and you’ll begin to see what I mean.

Of course, that doesn’t exampling how soap can be magnetic in the first place. For that, you’ll have to read on.

How Magnetic Soap Works

The moon, in the conservatory, with an iceberg

Image (and model) by Werner Willmann.

The 100th anniversary of Titanic’s fateful voyage arrives laden with new photos, new articles and, of course, new theories regarding what caused her sundering. Over the past century, researchers, authors and filmmakers have blamed the incident on everyone from White Star management and Belfast’s Harland and Wolff shipyard to Captain E. J. Smith and helmsman Robert Hitchins.

In this article, I examine the latest and arguably most novel theory: The moon did it.

Did the Moon Doom the Titanic?