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Comment Re:Seeking Technical Solution to Social Problem? (Score 1) 227

Meanwhile, in ten years, every tourist in DC will have a selfie drone

Which would be fine, except the DC FRZ (flight restriction zone) is a 30-mile circle around the Capital within which it is illegal to fly ANY remote control device of any kind. Includes "drones" as well as those toy RC helicopters at the mall kiosks, and the sort of RC planes that people have been flying around for many decades. Some tourist flying a quad in DC is in for a very rude awakening, as has already happened.

Comment Re:The things pump out plenty of RF. (Score 1) 227

Yea, but a cell phone signal flying over the south lawn is a pretty clear indicator that you have an issue

Wouldn't matter. Do you understand how small the White House grounds are, and how fast even a modest quad can fly when it means business? I've got one that can do over 40mph. That would cover the distance from the sidewalk in front of the White House to the middle of the typical speech-giving area of the Rose Garden in well under 8 seconds. A drone flying waypoints - with no need for a human controller nearby or watching - could be moving that fast well before it gets to the White House fence, and be coming in 200' overhead, be above a high-profile press event in seconds, cut power and drop like a stone spewing a mist of cesium or a nice cloud of serin or laden with a nice little brick of C4, and it would be on the ground in the middle of that speech/ceremony so fast you'd have no ability to do something about it. Except maybe light it up with some sort of automated buckshot gatling gun, right in the middle of a busy urban area.

This is going to result in a lot more events being held indoors.

Comment Re:I hate fear mongering... (Score 1) 227

I don't think that would work. After 9/11, the coverage showed unbroken windows removed from the rubble at the pentagon. The windows were designed to withstand a hit from any man-portable weapon system. This included the most powerful sniper weapons, as well as RPGs. I'm assuming the White House is no worse than the pentagon, but I didn't build either.

Comment Re:I hate fear mongering... (Score 1) 227

So we shouldn't place control on non-LOS 50+ lb drones because there exist 2 lb LOS-only drones? I can put enough C4 on a 2 lb drone to cause problems. The glass on the White House is designed to stop a .50 cal armor piercing sniper bullet. If you wanted to shoot the president, you'd be better off shooting through the wall. But a pound or two of C4 on a small drone, landing at the base of the wall may damage it enough for a clear shot, or dislodge one of the supremely heavy windows. Though I suspect that wouldn't work, for other reasons.

Comment Re:Impractical (Score 1) 597

If the connector was trying to provide 25 amps at 5 volts via the thin little wires, they would arc into gas almost immediately.

My phone charge does 5A at 5V without an issue, and my laptop doing 5A at 20V does so over tiny wires.

As an RV-er, I'm familar with both 12 volt and 120 volt systems. For a LED TV or other low wattage appliance, 12 volt is better, just because it directly comes from the batteries. However, for a load like a microwave, A/C, heater, or anything above 300 watts, trying to run that on 12 volts would require very fat, expensive cable.

You answer the question, then immediately forget the answer. You have AC at 240 (sigh, 110, if you must) and have outlets in some strategic areas (kitchens and for major appliances), and 12V or 48V everywhere else.

I think we should have a 48V internal wiring standard, with some 240V appliance plugs, for vacuums, refrigerators, washers and driers, and such. The dual-standard will complicate things slightly, but result in a large overall savings, as wall-warts are eliminated, and all their waste.

Comment Re:Premature (Score 1) 597

More sense is 240 AC for appliances, and 12V or 48V for everything else. DC-DC stepping in the wall jack isn't hard. So you go to the jack at 48V, and there to 5V for your wall-wart voltages. With some for 12V or 48V for higher powered things.

If it were me, I'd design a mechanical switch in the plug that activated the circuit, so it would have zero loss when not used, unlike current wall warts. We use 110 VAC because it's what we've always used, not because it's a good voltage or current type.

Comment 20% to 40% ??? No. Just no. (Score 5, Insightful) 597

To avoid the 20% to 40% power loss when converting from DC to AC

...they're doing it wrong. DC to AC conversion is easily achieved in the high 90% range. For instance, a typical solar inverter is around 95% efficient. And you can do better, it just gets more expensive (although that's a one-time cost, whereas energy loss is a constant concern.)

Someone is pushing some other agenda here.

Comment Still awesome (Score 1) 421

Sure. Did it to myself decades ago. Offspring of my genetic line aren't of the least bit of interest to me; perfectly happy raising kids of other birth who needed parents (5 so far, mostly excellent results.) Plus that whole "all the bareback sex with my SO we want, any time" thing is awesome.

Which, again, is just how I approach feline guardianship. Don't need new kittens from them. Plenty of kittens out there that need to own their own human.

Comment Re:You don't have to go faster (Score 2) 226

How exactly is space expanding, and what exactly is expanding into?

This is difficult to answer without getting into a long discourse on spacetime. However, you have to get away from the notion that there is some kind of "edge" to the universe and space is somehow expanding that edge into infinite nothingness. There is no "edge" to the universe anymore than there is a definable "edge" to our planet (i.e. a flat earth).

Comment Poorly written (Score 2) 226

Poorly written article and misleading summary. Basically the article says you can "travel faster than the speed of light" without violating relativity...but neglects to mention which "speed of light" you're beating. Light speed is different in depending upon what medium -- or lack thereof -- it's traveling through. It's possible to slow light down to the point where you can walk faster than that speed of light. But you're not violating relativity by doing so because you're moving through a different medium.

So, hyperdrives...not so much.

Comment Re:free... (Score 1) 272

You've said that the free lollipop given by a friend is free. Then you imply that the same exact lollipop transaction is no longer involving a "free" lollipop if your kid's friend stole it.

Free that requires unknowable knowledge of all previous owners of something before it's "gifted" to be able to determine whether it's free is a silly distinction.

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