No idea whether the new overlords will be any
better than the old ones, but the gnome is certainly sulky: he's ordered
his minions to take down the official website of the prime minister and
replace it with a fairly childish bit of text. Defeated indeed!
A bit over a week ago I mentioned that my washing machine has
decided to die - well, to forget how to spin-dry, which amounts to the same.
The off-balance detection was stuffed: it would start the motor in
high-speed mode but switch off after <1s, repeat 3x, give up
and hand me soaking clothes. (Same behaviour with an empty tub.)
The two-year warranty ran out a year ago (no surprise here). So I dismantled the machine and checked sundry other things (like inspecting/reseating the motor brushes) but couldn't find any mercury switch or other obvious means of detecting a bouncing tub. Accordingly, I couldn't fix it directly.
I have no precise idea how they detect an out-of-balance tub, except that the motor has a hall-effect rpm sensor which I think could work (assuming that the tub slows down and speeds up asymmetrically if it's wobbling). Net result of X hours of ripping apart, tracing wires and so on: all inspectables are fine but it still won't work. The only remaining part was the part-mechanical-part-electronic control board, and these things usually aren't cheap.
After a long search I figured out the proper part number (the fact that the machine is a rebadged Electrolux didn't make that search any easier), and would have been able to buy it online at various overseas retailers...for about $150-200..
Luckily ebay came to the rescue: somebody sold one as new-old-stock locally for $50. Add $26 for express postage, 10min for installation and I have a washing washer again. Very nice.
This was actually quite fun to build, a quickly gratifying small job:
how do you drive an LED from very little voltage (as in, a single 1.5V cell)?
You can't do it directly because leds need more voltage (at least 1.6V for
reds, above 3.0V for many/most whites).
So you need some booster circuit. Clive has a nice set of instructions for making what he calls a "Joule Thief", a simple inverter with three parts only: a centre-tapped inductor, a resistor and a transistor (He also has articles on other Must-Have Cool Things, like how to make a USB-powered turd).
For the ham-fisted among us, these guys show how to build the same setup with larger-sized parts.
I had a few minutes of nothing better to do this arvo, and built three variants with a fat 10mm white led: one hand-wound largish coil (2cm dia), one salvaged coil of similar size, and one smaller hand-wound one (0.9cm dia) with which the circuit wouldn't light up continuously.
For the adventurous, Dick Cappel has another set of really nice pages on similar projects, like the Rusty Nail LED inverter.
