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Comment: Re:Even if you go DC, stay at 120V (Score 1) 489

Everything from your wall switches to your wires will cause you never ending problems.

Mechanical wall switches are still rated for DC. Houses USED to be wired for DC a lot. You only have to replace the stuff that was designed after AC was pervasive and wasn't engineered to handle DC.

(I forgot to mention that you'll also have to replace the light dimmers, too, along with most other electronic, rather than mechanical, switches. They usually use a current-zero-crossing turnoff device, and DC won't cross zero unless you force it to do so.)

Even if you replace your wall switches and outlets, your wires will degrade over time and develop holes and other blemishes that will cause a fire.

No they won't - unless they're wet (in which case you have bigger problems than galvanic corrosion). Electromigration at the current densities involved in house wiring is not an issue, nor is insulation breakdown. The wires and fittings will be just fine.

Comment: Re:Even if you go DC, stay at 120V (Score 1) 489

(DANG this stupid touchpad... )

An "inverter", by definition, actually has alternating voltage as a substantial output, or at least somewhere in the circuitry. A switching regulator has a cycling voltage, but it isn't an AC output, or even an AC intermediate.

But they're very similar.

(Also: I was going to mention, above, that the current supplied through the pull-down (or clamp-at-ground) switch is where the extra output current comes from, compensating for the lowered voltage with higher current for similar amounts of power. If the switches, inductors, capacitors, and wiring were all ideal, the driver and sensor circuitry didn't eat any power, and no energy was radiated away as radio noise, efficiency would be 100%.)

Comment: Re:Even if you go DC, stay at 120V (Score 1) 489

A down-stepping DC-DC converter is not an inverter?

Nope. But the pieces of the implementations are similar enough in function that it's close.

A typical DC/DC down converter involves two switches, an inductor, and both input and output filter capacitors, plus control circuitry to sense the output voltage and time the switches. (There may also be a VERY small resistor in series with the inductor to sample the output current if current regulation is necessary, but it's omitted for high efficiency if that's not an issue.) One end of the inductor is hooked to the output cap, the other through the switches to the input cap and to ground.

The pull-up switch is always active (typically a transistor). The control circuitry turns it on and the current in the inductor ramps up, charging the output capacitor at an increasing rate. After a while the pull-up switch is turned off and the pull down switch is turned on. The current through the inductor ramps down, but before it goes through a stop and reverses the pull-up switch is turned back on and the pull-down turned off. The pull-down switch may be a diode, which switches on as needed automatically, but for high efficiency it's usually another transistor, because it has a lower voltage drop and thus is more efficient.

The control circuitry varies the percent of pull-up versus pull-down time to keep the average output voltage at the desired level. The frequency may be controlled or may be allowed to vary somewhat.

So the waveform in the inductor is a sawtooth, and the current never reverses. An "inverter" by definition,

Comment: Ronnie Phone (Score 5, Informative) 177

by PopeRatzo (#49795819) Attached to: FCC Proposes To Extend So-Called "Obamaphone" Program To Broadband

Just for the record, the "Obamaphone" program has a name. It's called the "Lifeline Assistance Program" and was started in the 1980s by...Ronald Reagan. It has nothing to do with Obama.

https://www.fcc.gov/guides/lif...

http://www.snopes.com/politics...

http://gawker.com/5947133/the-...

Comment: Re:Competition works better (Score 1) 230

When people talk about "we haven't returned to the moon" [bfy.tw], it refers to the end of the Apollo program.

So, the trips we've made to the moon SINCE the Apollo program (the most recent was in 2013), just don't count? Why is that?

Further, you apparently posted that "Let Me Google That For You" link without looking at any of the search results that Google provided you. The first link is to a Quora discussion about manned space travel, the second is a CNN article about whether we still need to have men on the moon.

So are you suggesting that only manned missions count as space exploration?

But then... your somewhat hastily provided Google resultsreally start to get interesting:

We get a YouTube video about extraterristrials, two pages from "Above Top Secret" and a website that suggests, "NASA is hiding a very dark secret from us" and that's why we haven't been to the moon. Then there's a link to a young adult Transformers novel on Google books and then a site called "Educating Humanity" which tells us the reason we haven't sent men to the moon is...aliens.

The next time you think to post a "Let Me Google That For You" page, you might want to actually check the links it provides to make sure they don't make you look like a complete schmuck.

Comment: Re:I got it! (Score 1) 109

I reallize the a person is going to take what the market will pay them, but it is seriously difficult to imagine that they are worth that much.

Then you really won't want to read about David M. Zaslav, from the Discovery Network and The Learning Channel (former home of the Duggar family and Honey Boo Boo) who's total compensation in 2014 was...$156 million!

http://www.cnbc.com/id/1026872...

It is good to be an oligarch.

Comment: Re:Competition works better (Score 1) 230

The fact that we went to the moon in "fucking 1969" is exactly the problem: it was a colossal waste of money. And the reason we haven't returned is the same reason: it still would be a colossal waste of money.

Um, we DID return, and multiple times.

Do you have any of your facts straight or do you just type with the seat of your pants?

First, you believed Columbus' voyages were "privately financed" and then you think we only went to the moon once. Give us a reason why anything else you say should be taken seriously if you can't get basic facts right.

Comment: Re:faster than light never violates Relativity (Score 1) 205

by Mal-2 (#49795085) Attached to: Ways To Travel Faster Than Light Without Violating Relativity

Even simpler, you point a laser pointer at the sky, and sweep it manually over a very distant target (bigger than the moon, but further away as well). Clearly your hand is not going to move faster than light, but the point where the beam finally hits something very well might. Again, this intersection is not a "thing", and cannot be used to communicate faster than the speed of light.

Comment: Re:Competition works better (Score 1) 230

For example, Columbus' Voyage was privately financed

And where do you think Queen Isabella got that money? She wasn't a tech billionaire. The funding came from the Spanish Royal Treasury. That means Spanish peasants paid for it and spoils of war paid for it and outright theft paid for it.

https://en.wikipedia.org/wiki/...

You think that solid gold throne Queen Elizabeth sits on when she's wearing her Imperial Crown that contains 2,868 diamonds, 273 pearls, 17 sapphires, 11 emeralds, and 5 rubies was paid for by the money that the House of Windsor made through honest labor?

danger is that the US government is going to interfere with private space exploration through ridiculous regulations and restrictions.

That US government you speak of derisively got us to the moon and back in fucking 1969. While the mighty private sector is barely replicating what the Mercury Program did over half a century ago. It appears John Galt is not only unoriginal, but he's kind of a fuck-up too.

Comment: Re:Heh. (Score 2, Informative) 222

People are still refusing to vaccinate children because they're afraid of autism even though the author of that study actually confessed having made the whole thing up.

Ummm... no, he didn't. There were a couple of issues with the study, the primary one being that a temporal association between the administration of the vaccine and the onset of autistic enterocolitis should never have implied causality. The study was important because it identified the colon symptoms present in a subset of patients with ASD as a distinct disorder. But it was misinterpreted in the press, especially for a study where the primary findings involved only 12 patients.

The main author never signed on to the minor retraction. There was nothing close to a confession of "making the whole thing up", but some (questionable) researchers from other institutions have made that accusation.

Comment: Re:Type C or mini B (Score 1) 76

by tlhIngan (#49794005) Attached to: Android M To Embrace USB Type-C and MIDI

As long as manufacturers do not start making Apple of themselves by having their own proprietary port, that's fine.

Rumor has it that the reason we have USB C is because of Apple. Basically Apple got fed up of the USB guys for having rather annoying connectors (especially ones that only go in one way - a royal PITA for mobile devices).

So rather than having yet another designed-by-committee connector, Apple basically gave it to the USB IF for free, with knowledge that it contains all the things Apple likes - like the ability to have A/V data sent through the connector, it fixes the nasty problem of well, having it only go one way, and it's symmetrical on both sides.

Probably Apple looked at what they did for USB 3.0 and decided it was fairly stupid, since now a USB 3.0 cable won't fit in anything other than USB 3 ports.

A CONS is an object which cares. -- Bernie Greenberg.

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