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Comment: Digital would be less "twitchy", but... (Score 1) 80

by Ken_g6 (#47889571) Attached to: L.A. TV Stations Free Up Some Spectrum For Wireless Broadband

Digital becoming twitchy isn't just because of transitioning to digital. It's also because they lowered the transmitter power.

The maximum power for DTV broadcast classes is also substantially lower; one-fifth of the legal limits for the former full-power analog services. This is because there are only eight different states in which an 8VSB signal can be in at any one moment; thus, like all digital transmissions, very little signal is required at the receiver in order to decode it.

So if you were watching an analog signal of the same power, you'd have a hard time making it out too.

Comment: Wireless charging (Score 1) 491

by Ken_g6 (#47867625) Attached to: To Really Cut Emissions, We Need Electric Buses, Not Just Electric Cars

This has to be one of the best use cases I've seen for wireless charging stations. Put one at every bus stop where it's practical. Just by sitting there, while letting people on and off or just waiting to get back on schedule, the bus can be recharging. Also, buses are long, so the density of power sent through the charging coils doesn't have to be as high as with a car.

Comment: Make a key component removable and portable (Score 1) 448

by Ken_g6 (#47826913) Attached to: Could Tech Have Stopped ISIS From Using Our Own Heavy Weapons Against Us?

For instance with tanks, if you make them drive-by-wire and you make the computer control system small enough, you can just pull the computer when you're done with the tank and take it with you.

Of course, the enemy could counter this in several ways. They could jerry-rig the tank to work minimally without a control system, but it would not be nearly as effective. They could steal the control computer, but that's a security issue - the key components should be under lock and key and heavy guard. Or they could steal the control software and load it on a smartphone or something, but that's again a security issue. And all of these require more technical knowledge than hot-wiring a car.

Comment: Re:Binoculars (Score 1) 187

by Ken_g6 (#47740233) Attached to: Slashdot Asks: Cheap But Reasonable Telescopes for Kids?

I got a pair of good 7x50 binoculars. As a side-benefit besides astronomy, I call them my night-vision scopes. When I look through them at dusk at terrestrial objects, everything I see looks brighter! You won't see the landscape when it's pitch black, but it's a surprising difference for unpowered optics.

Comment: Cheap helpers for cheap scopes (Score 2) 187

by Ken_g6 (#47740177) Attached to: Slashdot Asks: Cheap But Reasonable Telescopes for Kids?

Let's assume you got a cheap telescope. What can you do to make it work better for you?

1. Get astronomy software. Someone else mentioned Stellarium; I guess that's the go-to PC software now. I don't know what's available for phones. But make sure it shows an object's altitude in degrees.
2. Get a red flashlight. I guess these days people use red LEDs; back when I was a kid the place to go was army surplus for those bent army flashlights with colored filters.
3. Get a protractor. It's cheap, it's plastic, it shows degrees, and it's probably on sale now for back-to-school.
4. Get a piece of thin string and a weight, such as a nut for a bolt.

Tie the piece of string through the center hole on the protractor, and tie the other end to the weight. Now tape the protractor to the body of the telescope, preferably along some piece that sticks out near the tripod so it's aligned properly. To get an object in the scope, find its current altitude on your astronomy software. Then tilt the scope so the string's position matches that altitude on the protractor, using the red flashlight to see the string and protractor. You might have to do some math to get the matching number on the protractor. (90-x degrees - see, kids, that's what math is good for!) Now you mostly have to pan the scope, which is usually easier than tilting.

One other idea that came to mind while writing this: Take the jack stand out of your car, tape it to one leg of the tripod, and you might be able to use that for fine tilt adjustments. I've never tried this idea, though.

Comment: Re:Expert?? (Score 1) 442

by Ken_g6 (#47690405) Attached to: Is Storage Necessary For Renewable Energy?

He also doesn't get that even at a local level things like AC compressors are already averaged out and that delaying the timing of starts really makes almost no difference at the neighborhood level, much less a town level.

Averaged-out appliances are what you want with baseload generation. With fluctuating renewables, you want to be able to delay a significant fraction of appliances at the same time, for short periods when the generation is low, and start a significant fraction of appliances at the same time when generation is high. To do this, the appliances have to somehow receive a signal of when to start and when not to start, such as a price signal or a direct control signal from a utility. Users would still be able to have control, but could save money by sacrificing some control.

Comment: They're missing a lot of emissions (Score 1) 409

I notice that only gas is listed as adding new emissions. But hydro has methane emissions from the vegetation that's flooded when the dam is constructed. Not to mention the concrete that makes the dam. Solar, wind, and nuclear also have some building emissions costs, unless you replace all construction vehicles with electric and find a way to make concrete and steel without carbon emissions. (Wood might be an alternative for certain parts of wind turbines and maybe even solar frameworks.) Gas should probably have much higher emissions too, as the whole infrastructure from the well to the power station leaks methane. (How much is debated, but it's not zero.)

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