Warranty Void if Removed

A few weeks back I was thinking of ways to fuse electronics with jewellery. The first one I came up with was an LED on diamond. You could have a classical diamond ring with an LED built in the bulk. Gold contacts could be evaporated on, and could merge in nicely with the rest of the ring! ...

Thought I'd make my 3rd year project writeup available. It is a switch-mode power supply with digital PID control implemented in a low power microcontroller. The aim is to achieve a higher performance, more flexible design than a traditional analogue supply without the high power consumption of a high-speed DSP.

It scored highly, so might be worth reading if you're a 3rd year Electronic at Southampton.

In the early hours of this morning the Z-axis was completed. A new, much higher torque NEMA-23 motor from Motion Control Products (part FL57STH76-2808B ) was added, along with a length of 10x3 trapezoidal leadscrew and nut from Marchant Dice . In addition an adjustable mounting was added to one end of one of the guide rails to allow them to be adjusted perfectly parallel. Here are the results of a pen pretending to isolation mill a circuit board layout. Video:

Thanks to Paul I just remembered another idea. Since the UV laser pulses are too slow for laser use (on further reading, 50% duty cycle is massively optimistic), use an inkjet printer. Have the output of the UV air laser connected to a fibre, and stick the other end of the fibre where the ink cartridge lives. Add some focusing optics on the end, and presto. 

Need to modulate the output of the laser according to the make-ink-go-now signal, and we're away.

So the next question is power density...

Recently I've rather gone off the whole direct toner to PCB approach. Just doesn't seem to be robust enough. Having recently fabricated some PCBs in the Chemistry department I've seen some of the insane artwork they use. The artwork is (or was, before it was outsourced) produced in the university printing studio. The artwork is staggeringly good - incredibly black. High resolution too.

The process is as follows: 

The other day I thought "wouldn't it be cool if I could make an X-ray machine for reverse engineering PCBs, etc". So I looked around and found an ancient Scientific American article. It seems that all one needs to produce X-rays is an HV supply and an evacuated tube containing a cold electron-emitting cathode and some kind of target anode.

I am attempting to modify a laser printer to print toner directly to copper clad board. I'm quite excited about it, because it could be better than quite a few things...

Things are progressing rather slowly as my 3rd year project takes up more time. I was on the brink of keeping the printer happy through a complete print when suddenly the transfer belt lift clutch, cleaning roller cam clutch and feed motor all stopped working! I looked at the paper feed PCB, to which they are all connected and saw a small axial component the size of a standard resistor but without colour bands with "FU101" on the silkscreen.

I discovered a piece of software called Scribus. It is an open source desktop publishing program, and it allows one to work in CMYK space. I made a document with a black square made from 100%K and a "400% black" square, made from 100% of C,M,Y and K. Scribus allows you to use ICC colour profiles and display what your printer will actually print. I downloaded the 4550's colour profile from HP, plugged it into Scribus and sure enough the black square was lighter than the 400% black square.