Tag Archives: Power supply

Adding a current limiter to my MOT welder

Last year I built myself a welder using microwave oven transformers; I used it for a variety of things, but it was far from finished. Recently I’ve done some work to finish off the main transformers and to add a current limiting feature.
Improved welder Continue reading

Adding wi-fi to a Raspberry Pi without a powered hub

It is a commonly known problem that the Raspberry Pi cannot provide enough power for most USB wi-fi adapters. This can be solved with the use of a powered hub, however I have plans to integrate the Raspberry Pi into other devices; due to space constraints I decided that it would be better to convert a dongle to draw power separately to its data connection, also taking the opportunity to reduce the distance that it projects past the end of the board.
The modified dongle plugged into the top USB port of a Raspberry pi Continue reading

Making a mains adapter for a Canon Powershot A800

I recently bought a new camera; it’s a Canon Powershot A800. Although it’s only a basic compact camera, I specifically chose one that can run CHDK; this is a replacement firmware that allows access to just about every feature imaginable. One thing I wanted to try was to take regular shots over the course of a night so that I could combine them to create a photo of star trails. I quickly realised that powering the camera with batteries limited shooting to a couple of hours and the cost of batteries was going to start mounting up. With canon wanting about £50 for an official mains adaptor it was time to make my own. This is what I came up with:
The AC adapter and the completed camera lead Continue reading

Building a 10kV DC power supply

It’s time for the first post filed under ill advised experiments. Just in case you’d not got the hint from the name, don’t try this unless you know what you’re doing; one small slip and the only silver lining will be the cut-price cremation you’ll get for half doing the job yourself.

I’ve spent the last week building a 10kV DC power supply capable of about 100mA. In the main part it is composed of a microwave oven transformer(MOT), 4 microwave oven diodes and 60 camera flash capacitors. Continue reading