The Dead Computer contest over at Instructables is over. It’s easy to find the winners, but it’s some work to dig through all the also-rans to find the overlooked gems. Fortunately for you, I have performed this task and present what are, in my opinion, the Best of the Instructables Dead Computer Contest Also-Rans. That’s a working title.
There are three power-supply-fan-as-fume-extractor projects, a simple to build and useful addition to any workbench. These generally involve a box, a fan, and an activated charcoal filter. I think all of them need more ducting in order to really evacuate soldering smoke from a work area.
Many of the entries involved turning computers into appliances. There’s a project that turned an obsolete Silicon Graphics server into a small refrigerator by removing the guts and installing a small dorm style fridge. Another entry used an obsolete CPU as a small hotplate. To make the hotplate the author removed the CPU from the motherboard (It’s a PGA package, which makes this a very old CPU), found the power and ground pins from the data sheet, and soldered the power pins of a cut up USB cable to them such that it turns on when plugged into a USB port. The whole thing is packaged up in a nice box with a CPU fan guard over the top. You only get a couple watts this way, but maybe that’s enough to keep your tea warm. There is also a scope made from a CRT. For this project the author opened the case up and connected an audio amplifier to the Y deflection coil, while leaving the X coil connected to the sweep circuitry. The monitor itself is connected to a computer that only partially boots. The video display from the computer (it doesn’t matter what is displayed, you just need the sweep signals to be properly driven) is compressed into a single line which is modulated by the output from the audio amplifier, which in turn is connected to the signal you want to view. Since the Y coil displays the signal, the monitor has to be flipped on its side. Clever, but ultimately not that useful.
Other entries were to turn computer parts into toys of various types. There’s a computer mouse that runs away just as you’re about to touch it. It uses a light sensor to detect your hand and a little motor that makes it scoot. Another clever entry is a computer mouse robot that is able to avoid obstacles. It is driven by two motors and wheels, and uses the mouse buttons to tell when it has run into something. When it does it backs up or turns and keeps going. Other toys in the contest are a Rubik’s cube made from keyboard keys, a “rock’em sock’em” type mechanical boxing game built from a VCR (and using the mechanical bits from the loading mechanism for the robots), and a hovercraft built from a power supply’s muffin fan. This last one runs the fan at 36V in order to move enough air, so if you want to use it a lot you probably need to have several more fans as backups.
Lastly there were several artsy type submissions, including fan guard art for the garden, a stylish “touch” light dimmer that uses a hard drive platter for the touch surface, and a desk clock made out of a hard drive.
Hope you enjoy reading about at least some of these,
Steve Ravet
EDN Gadgeteer
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