Saturday, March 14, 2009

The repair shop

One of the annoying things about modern home electronics is that they are black boxes. Like a microwaver, cold food in, push buttons, warm food out. Who knows what happened inside?

Most people are probably happy they don't know. But a life without curiosity is a life with less passion. I was fortunate enough to get an excuse to take apart two home appliances recently because they broke. And it wasn't even my fault.

The first successful repair was Janne's younger sister's laptop. The power chord had been loose for some time, at some point the laptop simply stopped working with symptoms of no power.

The anatomy of the repair is not too far from debugging software you don't know (I've previously talked about debugging software you've written yourself). Take the system apart, examine the individual components, collect information, reason. Identify the faulty component and apply the easiest fix you can think of.


Taking apart the laptop


The faulty component, the switchboard that the power chord plugs into (visible at the finger tip)

I had an edge here. I'd heard about this problem before. So instead of giving up beforehand, it got me thinking that if it was a common problem, the remedy would probably be well-known among electro-hobbyists. A bit of googling revealed that some people had success with soldering off the small house the power jack is inserted into, and replacing it. When we examined the house, something was in fact wrong with it, as witnessed by a simple currency test with a multimeter.

So we set out to solder it off. Unfortunately, that didn't work out. The soldering metal wouldn't melt properly. Instead we ended up replacing the whole component, i.e. the small part of the mother board that the ports were sitting on. The web is extremely handy here. Just jot down the spare part number and search for it, or parts of it.



We ordered a spare part which ended up costing less than 1/10 of the price of a new laptop, and put it in.

In reality, this was a bit harder than it sounds, because the first two places that turned up on the web didn't actually have the part when we tried ordering it. Also because taking apart a laptop is a bit complicated because of all the tiny screws and chords and plastics that have to be bent in awkward positions, sometimes more violently than you'd like to think about.

Last week, I had a much nicer experience changing the BIOS battery on my trusty old Pentium III laptop. Ugly looks, but nice internals.

Continuing on this saga, I've also fixed our microwave oven. Microwave ovens are a bit more complicated in the feature set than I hinted above. They also make the food turn around, slowly. But our oven stopped doing that. So I took it apart, hoping that it would be a bad connection.



One non-rotating Samsung microwave oven


The faulty component in the microwaver

However, there was nothing wrong with the connections inside the oven. The funny thing about hardware is that as soon as you take off the shell, it looks complicated and futuristic, but in reality it's just a set of interconnected smaller components. In this case, the sealed turntable motor was broken. Again, with the component number it wasn't hard to find a spare part on the web.

However, this presented me with an interesting real-life dilemma. Is it worth 22 £ to me to be able to see the food inside the oven carouseling past? My first answer was no. I already got to see the oven inside, it's actually pretty simple, and identify the problem. I didn't have to actually fix it.

A couple of weeks later, the oven fried a very useful corn bag we're using to loosen stiffened neck muscles, a useful cure for some kinds of head-aches. The oven had burnt a hole at one particular spot in the non-rotating bag.

So today I installed the spare part. Works like a charm.

This may sound silly, but fixing supposedly unfixable things is really rewarding. You feel powerful and virtuous.

A couple of extra garden pictures:


Enjoying the spring sun at noon


Next day it's snowing

2 comments:

  1. Repairing appliances and hardware are a big work to do. It also consumes time and effort.

    ReplyDelete
  2. Based on my experience I'd say you're right on all three accounts.

    But even so, it was great fun, most of the time.

    ReplyDelete