Monthly Archives: April 2012

Controlling the mains with bluetooth proximity

I’ve found another use for my parallel port controlled socket box; by using it in conjunction with a bluetooth dongle, I can detect when I have wandered out of the room. I can turn off a load of peripherals, then turn them all back on when I return to the room seamlessly. I’ve simply plugged the extension leads which power my monitors, speakers, kettle, lamps and fan into the parallel controlled socket then let a ruby script act as the brains of the operation. Continue reading

Building an arc welder from microwave oven transformers

I’ve spent the last couple of weeks building an arc welder by winding new secondaries onto two microwave oven transformers (MOTs). The one important lesson to learn from all of this is that high power transformers are not a place where the “fuck it that’ll do” method works; I wrecked a couple of primaries so ended up having to find fresh MOTs and start again. Continue reading