ego.istic.org

Browsing (if you'll forgive the pun) the Kevin and Kell archives, I came across this comic. Does anyone else think that this design would be awesome? All you'd need to do is buy one of those cheap WiFi detector keyrings, and mount it inside a hollowed-out, Y-shaped stick. For the true feel of being able to point with it, you could make the straight bit into a directional antenna, and for extra bonus points, replace the buzzer (or whatever it uses to show that it has found a signal) with a vibration motor from a mobile phone.

Let's face it, Holbrook's cartoon does have a point here. The limitation of our species that we can't sense radio waves directly is exactly what makes them useful for communication, but also what makes it so hard to track down problems.

When I was working for a company that made a product based on 2.4GHz and ultra-wide-band (UWB) radio, this was a problem that often faced us. With different people in the same building trying different ideas, it was all too easy for one person to forget they'd left a transmitter turned on and blasting out radio noise over everyone else's tests. Tracking down noise sources got much easier after a bright soul added a feature to the software to display a graph of the raw signal levels picked up by the receiver. This, combined with the strongly directional sensitivity of our UWB receivers, led to a new method of finding noise sources. After that, a common sight around the office was one person wandering around brandishing a receiver attached to a long Ethernet cable trailing behind him, with another standing at a nearby machine shouting out how ‘warm’ or ‘cold’ they were getting.

Another optimisation came later, when the fixed receivers in the corners of each room were upgraded to support this new feature. After that, one person would watch the graphs for all four sensors in an office while the other would walk around holding a steel tray in front of each sensor in turn to shadow particular directions in a process of elimination.

For an observer with no knowledge of the internals of the system, or poor understanding of physics and the propagation of radio signals, these techniques would look no different to divination, which I suppose is just another example of Clarke's observation that “Sufficiently advanced technology is indistinguishable from magic.”

By merest coincidence, OED's most recent quarterly update adds 22 new headwords starting with “radio-,” and 40 new sub-entries to existing “radio-” words and phrases. “Radiodivination” is, alas, not among them.