Tuesday, 9 March 2010

Wild Wales

I've just finished reading Wild Wales, by George Borrow, which I picked up in an Oxfam bookshop for £4.99, not long after we moved over here. I know this because I've been using a train ticket (Day Travelcard between Earlsfield and zones 1,2,3 and 4; dated 22 October 2006) as my bookmark, which is quite convenient.

The book, first published in 1862, is a telling of Borrow's (mostly) walking tour of Wales, in 1854. He starts off in the north and covers much of the country, inexplicably missing out most of Carmarthenshire and all of Pembrokeshire as well as Cardiff.
I won't give a full review, but it is an interesting look at Wales, right at the beginning of its industrial boom. I particularly appreciate this passage, describing his arrival at Merthyr Tydfil at night, at a time when (I believe) my great-great-great-grandfather, Thomas Hughes, was living there:
Turning round a corner at the top of a hill I saw blazes here and there, and what appeared to be a glowing mountain in the south-east. I went towards it down a descent which continued for a long, long way; so great was the light cast by the blazes and that wonderful glowing object, that I could distinctly see the little stones upon the road. After walking about half-an-hour, always going downwards, I saw a house on my left hand and heard a noise of water opposite to it. It was a pistyll. I went to it, drank greedily, and then hurried on. More and more blazes, and the glowing object looking more terrible than ever. It was now above me at some distance to the left, and I could see that it was an immense quantity of heated matter like lava, occupying the upper and middle parts of a hill, and descending here and there almost to the bottom in a zigzag and tortuous manner. Between me and the hill of the burning object lay a deep ravine. After a time I came to a house, against the door of which a man was leaning. “What is all that burning stuff above, my friend?”
“Dross from the iron forges, sir!”
I now perceived a valley below me full of lights, and descending reached houses and a tramway. I had blazes now all around me. I went through a filthy slough, over a bridge, and up a street, from which dirty lanes branched off on either side, passed throngs of savage-looking people talking clamorously, shrank from addressing any of them, and finally, undirected, found myself before the Castle Inn at Merthyr Tydvil.

Monday, 22 February 2010

GPS: Working! (well, nearly)

So I got my GPS module working.. sort of. After stuffing around with it for ages it turns out I was just being daft, and after fixing several obvious problems in both hardware and software I was getting lovely NMEA codes out:
The $GPGGA line is positioning data and the $GPGSV lines are data about the satellites we can see. Unfortunately from the flat we don't have enough sky view to be able to get a fix. The GPS is only tracking one satellite which is only good enough to give us the current time as shown in the first line (20:24:29).

Next plan is to write some software to do something useful with the data...

Wednesday, 17 February 2010

Homemade Toner transfer PCBs

We've just recently bought a laser printer so I've been trying to make some decent printed circuit boards with the toner transfer method, where you take a reversed printout of your circuit and iron it on to plain copper-clad board, then etch the board and the toner resists the etchant, and the circuit remains in copper on the board.

That's the theory anyway, but finding the right paper is a problem. You need a glossy, waxy paper that will easily come away from the toner when you are done ironing, but most papers just fall apart and you are stuck with half a sheet of paper firmly attached to your circuit-board-to-be.

Many people on the internet seem to use magazine pages, but I have found them to be uniformly rubbish for fine-pitched traces.

For future reference, the following papers don't work:

Buzz (Cardiff gig guide)
Guardian Weekend Magazine
New Scientist
Look Magazine
Cotswolds catalogue
Domino's Flyer.
Tesco "Value" glossy photo paper
and regular Kitchen Paper, which I thought would work well, but doesn't seem to want to release the toner onto the copper.