laptop on 12 volts
Monday, December 20 2010
For years I've been thinking about replacing the crappy multifunctional Aiwa CX-ZR774U stereo that has been our living room's only form of electronic entertainment. I hate that stereo with a special passion, mostly because of all the user interface decisions it gets so profoundly wrong. The unit is entirely digital, though it attempts to emulate some analog functions with a couple large multi-function knobs. The problem with that is that when you need to turn down the volume quickly, you never want to be in doubt about the function of the large knob that normally handles that behavior. There is no potentiometer behind the knob; instead there are a set of switches that indicate how many degrees it has rotated and in what direction. Unfortunately, one of those switches began failing several years ago and it's become impossible to make the volume do anything except increase unless one resorts to using a remote. Then there's the issue of power; the stereo cannot be powered down without unplugging it. When it's off it continues to consume 15 watts of power while showing a simulation of some sort of meaningless slot game on its vacuum fluorescent display. That alone is enough to make me take it out in the back and smash it with a splitting maul.
So I've bought a nice Sony stereo to replace it with, but I'll also need some way to play CDs (which Gretchen still uses) and MP3s. Some audio can be picked up via FM radio (which both my computer and — to a lesser extent — Gretchen's computer can transmit), but it would be good to be able to set up a playlist there. The cheapest solution would be to have a computer there that I could use, ideally one that could easily go into standby. It would have a reasonably-large hard drive preloaded with all the MP3s we'd want to be able to play and it would have a CD drive and perhaps places to plug in thumb drives and smart media cards (a much easier way to carry music around than optical media and one our household already uses to get MP3s from the house to the cheap — though customized — Chinese MP3 player in the Honda Civic).
I've had an old Toshiba 2250CDT I've been wanting to make into an MP3 player for years, but old computers have their own problems. This one only supports USB 1.1, so its one PMCIA slot needs to be occupied by a USB 2.0 card which then must be occupied with some sort of USB WiFi adapter and perhaps a USB-to-ethernet adapter, as well as a USB-to-IDE connector for a desktop hard drive (I don't have any large-capacity laptop hard drives). These complexities were becoming so absurd that I briefly experimented with an old AMD K6 motherboard (technology that would have been current in 1999). But it used 50 percent more power than the Toshiba laptop while running 50 percent more slowly, and I couldn't figure out a way to attach the K6 motherboard to a WiFi adapter (though I have hardware that should have worked).
So I returned to the Toshiba, trying to figure out a unified way to power both the desktop hard drive and the laptop without having a profusion of power supplies. So as an experiment I tried running the laptop directly off the 12 volts coming from a desktop power supply. This was somewhat less than the 16 to 19 volts laptop power supplies usually provide, but it turned out to be sufficient. The display didn't even seem to shine dimmer. This discovery will greatly simplify any computer-specialized-as-audio-device I might choose to make, because it will allow me to drive the whole thing (storage devices, USB hubs, laptops, etc.) from a conventional desktop computer supply. (Mind you, I've run laptops off 12 volts in the past, but they were considerably less advanced than this Toshiba; also, their displays ran substantially dimmer.)
A desktop power supply seemed like bulky overkill for a project that was never going to need more than 50 watts of power even at peak load. So I tried out a small power supply of the type used to power external hard drives, but it didn't supply quite enough power. Though they're bulky, the good thing about computer power supplies is their efficiency. Indeed, I could probably disconnect the inevitably noisy fan in an old computer supply and run it fanless at my power needs.
At some point today I thought I'd use a ladder to climb into one of the more distant White Pines south of the house so as to prune branches blocking winter sunlight to our house. Even at near-solstice, the branches doing this blocking were high in the tree. I climbed some of the way past the top of the 24 foot ladder using stout lateral branches as ladder pegs, but these were dead and they made me nervous. I wasn't entirely trusting my life to the dead branches, but there was no way to climb without putting weight on them. Still, they were pretty stout and I probably could have climbed all the way to the canopy and done what I'd set out to do, but I chickened out. I don't have a true fear of heights, but I panic a little when I'm up high and don't have a straightforward way to proceed.
This afternoon and evening Gretchen had a meeting with the woman with whom she is collaborating on a book that has already been sold to a publisher. That left me alone to fend for myself. I had a hankering for tacos, so I cooked up a big pan of onions, Portobello mushrooms, and black beans. It seems that I had too many mushrooms and onions and too few beans, because the resulting concoction ended up tasting kind of gamey. It's a hard thing to describe, but try to imagine something that should taste a lot like beans tasting instead like it has lots of onions and slightly-past-their-prime mushrooms in it.
I was kind of desperate for teevee after I'd made myself tacos, so I ended up watching American Chopper, a reality show on the Learning Channel about a shop that makes customized motorcycles. It's kind of a meathead show, but it's also got fun metal working porn in it. Still, it's nowhere near as good as, say, Storage Wars or even Gold Rush: Alaska.
Later Gretchen and I watched a DVD of The Town, a heist thriller that is not actually out on DVD yet (Gretchen borrowed it from a friend who has an Oscars vote). I'm a sucker for a good heist movie, and enjoyed it thoroughly.
Clarence with Sally's legs in the foreground.
Nigel. He's recently gotten over the mental block that largely confined him to the basement (a block based in large part on his antipathy with Julius — aka Stripey).
Nigel and Eleanor enjoying the fire.
Eleanor really enjoys a hot fire. She often wears a purple jacket at this time of year because her fur is so thin.
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