sea of shoplifting information
Tuesday, January 9 2007
The two purebred Standard Poodles we're dogsitting for the next two months have an unexpected problem we'd been warned about but which I'd thought would be an occasional problem at worst. They may be geriatric, but one or both of them isn't fully housebroken. Being old dogs, there's not much hope of teaching them the new trick of holding it until they can go outside. Or, for that matter, that the outside is easily reached through the pet door. The lack of housebreaking is proving to be more of an issue than originally feared. Today was the second day in a row that I found a puddle of urine near the wood stove. By today this urine was causing a visible cupping warp in one of the floor boards. I cleaned it up and put down plastic, which will have to stay there for the next two months.
Meanwhile, a majority of the cats seem to have adapted to the presence of the two dogs. Marie was the first, then Clarence, and now even Wilma will risk walking across the dining room when the dogs are nearby. But not Julius or Sylvia. These days those two spend most of their time in the laboratory, where they can always escape behind an old monochrome green IBM monitor. I've started keeping cat food, water, and even a litter box up there just so neither ever needs to venture into scarier parts of the house. Julius actually is a little bolder than Sylvia and will lounge around in the teevee room when the dogs are downstairs. But poor Sylvia is still in that phase where she slinks about on tiny inch-long legs whenever uncertain of the dogs' whereabouts.
I had a lot of programming to do today, so I spoiled myself by preparing a Freedom press full of freshly-ground coffee. Unless you count a machine-made cappuccino I'd had in Allentown, it was the first coffee I'd had since December 23rd, which was the first coffee I'd had since November 13th. The coffee felt great at first, and seemed to strap rockets onto my productivity and focus. But then later in the day I felt myself become physically jittery and cognitively obsessive. In the end I was forced to drink alcohol to settle myself down.
While in that obsessive phase, I finished work on that knife I'd begun yesterday. In the end I made a little plastic hood for the blade out of slit piece of clear vinyl tubing. Pivoting on a piece of bent copper wire passing through a hole drilled in the blade, the hood can be snapped over the blade, allowing the knife to be carried safely in a pocket. Then, when used, the knife is drawn across a surface, which causes the hood to snap back and expose the blade. By the way, drilling a hole in a utility knife blade requires an extremely hard bit; I couldn't do it with anything softer than the kind designed for drilling through glass, and I destroyed that one in the process.
Since my new knife is the kind that a shoplifter might keep in his toolkit, working on it inevitably led to a surfing safari on the sea of shoplifting information available online. At first (as the NSA has doubtlessly logged) I was interested in the toolkits used by professional shoplifters. But then I became interested in the technology used to sound alarms when people neglect to remove theft-prevention tags from the things they shoplift. It turns out that I have a couple of the acousto-magnetic tags around the house. One was actually inside the handle of a cheap Skil powerdrill that I'd bought in a Saugerties hardware store. Another was in a box of rubber washers that had set off an exit alarm (so I know it is "activated"). I couldn't find any that I knew to be deactivated, but I'll be sure to save them in the future. Using a compass, I established that an activated tag has a detectable magnetic field. But what I really wanted to do was make a device for finding these devices. They have a resonant frequency of 58 kHz, so if I could make a 58 kHz oscillator energizing a coil, perhaps I could make activated tags resonate in a way detectable by a separate circuit.
Making an oscillator for a specific frequency is easy if you have the crystal. But as far as I could determine, 58 kHz crystals are not available anywhere. I would have to create the oscillator some other way. This led me to do some experiments in the Arduino environment. Perhaps an Atmega8 could be programmed to pulse one of its pins at 58 kHz. A found a post in the Arduino forum that gave me hope (one guy got the Arduino to generate a 497 kHz signal) but then my experiments suggested that the best I could do was 10 kHz.
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