A Mythbuster's Biggest Tech Headaches (and Solutions)

An anonymous reader writes "The Mythbusters' Jamie Hyneman shares his top tech annoyances. Hyneman runs down the little things that bug him about everything from tools (exotic chargers) to cars (useless features). He also notes that there's a lot of room for improvement on PC desktops: 'In addition to being buggy ... extra features tend to bog down your system by demanding more processing power and memory. Computer-makers: Don't load up operating systems with features and then make us sweat to figure out how to get rid of the fat ... There's another solution available to consumers: Switch to a Linux-based OS such as Ubuntu. Since most Linux OSs are free, there's no business reason to bloat up the system with feature frills.'"

Comments

Re:Things will be getting simpler, and are already

[Technician]

In my car I tossed the 12V "cigarette lighter" from the dash to the truck. I also increased its power from a small 5A fuse to a 10A fuse, so I can run a reasonably sized 120V inverter (also in the trunk) to power a few devices on-the-go.


Drawing twice the power than the wire was fused for is a good way to need another car soon. Unless you also upgraded the wire, I wouldn't recommend changing the fuse size.

I have a reasonably sized inverter in my trunk also, next to the battery. 1KW will power most anything except hair dryers you care to bring along.

At home, we have a DC run throughout the house wherever we upgraded our power,

This is not a good idea. Volts X Amps = Watts in DC circuits. To run a 100 watt laptop cross the house on 12 volts with less than 10% voltage drop requires a huge wire. Do the math.

http://www.otherpower.com/cgi-bin/webbbs/webbbs_config.pl?noframes;read=6346

Don't forget a 50 foot cord is a 100 foot DC path.

To cut your loss in the wire by 100 as in a 10$ loss is now a 0.1% loss, go from 12 volts to 120 volts. That is the simple reason for the big inverter in the trunk. I can run a 100 foot 14 AWG extension cord and have less than 1% voltage drop in the cord to a 100 Watt laptop.

From the page "14AWG = .00297 ohms / foot". Doing the math, a 100 foot 14 gauge extension cord is 200 feet of wire with a resistance of .00297 ohms per foot. 0.00297 X 200 = 0.594 ohms. To get 100 Watts at the far end of the wire at 12 volts, you need to deliver 8 and 1/3 amps. That amprage going on that almost .6 ohm wire will have a voltage loss of 0.594 X 8.3333 or 4.9499 volts. To get 12 volts out, you need to put in 12 + 4.9499 volts. Volts X Amps in the wire is the power lost.. Let's see, lost 4.94 volts along 200 feet while carying 8.3333 amps. That's 41 Watts. In short to drive a 100 watt load, you toss out almost 1/3rd of your power in the wire.

Now using the same cord and laptop but now using 120 volts. Instead of needing 8.3333 amps for the 100 watts, we now need 1/10 of that or 0.8333 amps. Our voltage loss is now 1/10th what it was or 0.49499 volts at 1/10th the current. We now lose 1/100th the power in the wire we were before while still delivering 100 watts to the laptop. Now the wire has a loss of 0.41 Watts. I don't need to boost anything to make up for it.

I'm shocked that more devices aren't standardizing on DC. 18V, 5A+, not a big deal -- but so many devices could use it (charging tools, video games, cell phones, even some computer monitors). Simple, without needed ANOTHER heat-generating and wasting transformer. My laptop is DC, too, yet I need the darned transformer throughout the house.

Do the math and you won't be shocked at all. I would rather lose 5 watts in a laptop power supply than 40 watts in the 50 foot wire from the battery fuse box to the laptop.

I've standardized on 120 VAC for almost everything. As a bonus, I don't have to buy special 12 volt CF bulbs at $15 each. I can use the buck a bulb ones instead. It's all about saving money. A 1 KW inverter is chaep and can be located very close to the battery to keep loss minimum in the low voltage wire.

http://www.costco.com/Browse/Product.aspx?Prodid=11234952&search=inverter&Mo=13&cm_re=1_en-_-Top_Left_Nav-_-Top_search&lang=en-US&Nr=P_CatalogName:BC&Sp=S&N=5000043&whse=BC&Dx=mode+matchallpartial&Ntk=Text_Search&Dr=P_CatalogNam