I've got a new toy: a Tektronix 2246 ModA, for about $500 (incl. shipping from the UK). It's really nice (100MHz, 4 channels, analog but microcontrollered, hence nice measurement and cursor features).

Current project: making a very obnoxious and loud doorbell with a PIC. I came up with the necessary microsecond-precision delay routines and the remaining frequency generation stuff, and a bit of perl took care of eating a MIDI file and barfing out suitable frequency and duration information in PIC assembler.

The last insanely horrible tune I've been trialling: "Innsbruck, ich muß dich lassen". Sounds perfectly ghastly when a cheap piezo is squarewave-squealing its guts out. I'm also thinking about using "Tirol isch lei oans" just to remind me why I'm here and not there.

Here's a pic of the latest test setup: I'm currently learning how to use an inductor to boost voltages (and how a common collector amplifier works). Messy but fun.

[ published on Wed 28.03.2007 02:33 | filed in interests/tinkering | ]

(Clearly not.) But nevertheless, this is a very interesting article about Fitts' Law and how interface design should be affected.

Some of the assertions seem...unfitting, though: for me, moving the mouse to the bottom is the most annoying move, not the least: the mouse
has to travel beneath my palm and wrist (I tend to control the mouse with my fingertips and a bend of my wrist and rarely ever lift my elbow off the desk.) Moving to the top I just extend my fingers, so that's faster.

But then I'm weird: I have the mouse on either side, with some bias to the left -- but I'm somewhere between righthanded and ambidextrous otherwise, I switch between two different keyboard layouts every day (german at home, english at work) and so on.

[ published on Tue 27.03.2007 00:53 | filed in interests/comp | ]

Brutish Airways recently had someone old kark it in the air. The cabin staff moved the ex-passenger to first class, propped her up in a seat and that's it. Move on, nothing to see.

The article in the Times is pretty hilarious, discussing the "disturbed" snobs in 1st. Come on, what else could they have done? Turn around just because of a stiff in cattle class? "Bomb's away"?

The part I liked best is this: "After the plane landed, those in first class remained on board for an hour before police and a coroner gave the all-clear." Heavenly Justice rules! The rich snobs get to leave last for once! hehe

As to BA, having body bags on board might have been a Good Idea. And I'd have plonked the dead in a toilet, and locked that, but of course 1st class is almost as good a place to dump a slowly rotting corpse in.

Link to the Times article

[ published on Mon 19.03.2007 09:57 | filed in brainfarts | ]

I complained about bank logins a number of times, the last one being citibank's mouse mess. Apart from that I have no major issues with their credit card service...except the insistence on a PDF plugin to read your statement. WTF?!

Well, now they can insist as much as they want because I wield the Greasy Monkey wrench...and I win! This greasemonkey script neuters the plugin-insisting code and also converts the EMBEDded (spit!) PDF into a normal plain link. Works for Citibank AU, maybe other incarnations. (BTW, userscripts.org sucks, I lost my password and can't reset it, thus this script will not end up there anytime soon.)

[ published on Sat 17.03.2007 21:13 | filed in interests/comp | ]

why are there days when nothing seems to work out? When you end up in the arvo/evening with a big fat zero on the day's tally? And why do I have oh so many of these days? I'm so sick of this...

[ published on Sun 11.03.2007 18:28 | filed in still-not-king | ]

...cupboard doors into desks, IBM Thinclients into music boxes and all politicians everywhere into dead politicians. I'm all for it, and I did my part for the doors and the music player. (And just for the bloody record, let's get rid of all the governments, too. Yay for Anarchy! I'm in a bad mood today, as you can surely tell.)
click here for the rest of the story...

[ published on Sun 11.03.2007 15:35 | filed in interests/tinkering | ]

...in addition to flying yourself. I have a new toy, for the days when it's not nice (enough) to fly myself. But like all the toys that I like, it requires loads of tinkering and a little bit of skill. It's a radio-controlled glider.
click here for the rest of the story...

[ published on Thu 01.03.2007 23:51 | filed in interests/flying | ]

Here's some recent projects/happenings. For my new RC plane I needed reasonable charging facilities, because most trickle chargers like the one I got with the RC gear are trash. So after some thinking about building my own charge controller (not too tricky but time-consuming) I bit the bullet and bought this SJ Propo Swallow Advance charger: a very nice bit of equipment, charges pretty much anything from Lead-Acid to Li-Po intelligently, and with nice options. $90, so not exactly breaking the bank.

But the Swallow is DC only, 11-15V, good for taking with you in the car, bad for at home. I hate wallwarts. So I need: DC, preferrably 12V at 3-5A. But I have: loads of lousy underpowered wallwarts (bad) and loads of old garbage (good). Because the old garbage contains the innards of a few Sun SCSI enclosures, some of which came with brilliant fanless Sony-made switching PSUs. APS-28: old, silent, solid, juicy and saucy :-)

Time for the tinker: it simply took a few galvanised nails, some foam and a bit of soldering to convert the Molex outlets to posts for crocodile clamps. (There is extra insulation behind the foam, but the sparkies wouldn't be too happy with the design. Screw 'em!)

 2007_03_01-swallow-psu-bare.jpg  2007_03_01-swallow-psu.jpg

That PSU now also replaces three wallwarts, which makes me really happy. I fabricated some custom charging leads from scrap (old wires, some computer connectors, crocodile clamps from rotten test leads etc.) next: one 12V lead for the Yaesu VX5R which has its own charge controller (Li-Ion) and a tiny plug, one 12V fat plug for the CDMA phone's charger-stand (with its own controller).

The fat plug also works with the cordless drill, now and only after I gutted the drill charger stand: first I connected the Swallow to that, but the stand actually contains a few resistors for trickle charging. The Swallow blasted a few Amps at about 19V across that, the resistor got a tiny little bit hot, the stand plastic started growing surrealistic in shape and I quickly stopped things before the Magic Smoke got out. Now: gutless stand, brains in the charger. Me happy.

Another recent successful tinkerproject was modding Guntis' radio: he wanted a remote PTT switch to connect to his small speaker-mike sitting on his shoulder, just like the setup I've used for the last two years. (My new in-helmet setup was tested on Sunday and works superbly.) So I hunted up parts, traced the wiring in his speakermike and Simply Dit It. First I rewired the speakermike to activate on the PTT switch, and then I built a new remote PTT switch from scratch.

Here's the switch I made for him: 100% recycled components! :-)

 2007_02_25-guntis-ptt-side.jpg  2007_02_25-guntis-ptt.jpg

The switch is a leftover from a dead computer mouse that I desoldered, the cable with conveniently moulded-on mono plug comes from a first-crap-then-defunct $50 "stereo system", the button (for improved tactile feedback with gloves) is from the sewing kit my great-aunt left me, and the velcro was a leftover from some other project. Even the idea for the switch is recycled: this guy had it first :-) (Ok, solder, superglue and shrinktube were new. Sue me.)

And the next projects are already on the horizon: exploring the wonderful world of PIC microcontrollers. These things are cool! (I recently spent about $250 on a better multimeter and a bunch of chips, and may soon spend another up-to-$800 on an oscilloscope. Learning electronics is fun, but getting a reasonable set of tools is not -- for a money-concious person like me.)

Here's my first pic circuit: it toggles the led state on every switch activation, debounced in software. Looks like nothing, better stuff to follow soon because I've got shitloads of wacky ideas that I want to implement...

[ published on Thu 01.03.2007 23:21 | filed in interests/tinkering | ]

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