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Comment: Re:Even if you go DC, stay at 120V (Score 1) 500

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) 500

(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) 500

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: Re:Ronnie Phone (Score 3, Insightful) 198

by Tablizer (#49795999) Attached to: FCC Proposes To Extend So-Called "Obamaphone" Program To Broadband

It's odd how it seems to politically matter who does something more than what is being done. Examples:

"GOOD" (or neutral) WHEN BUSH DID IT:

Corporate welfare
NSA
TSA
DHS
deficits
stimulus
bombing
medicare part D
golfing
hugging Saudi oilers
saluting with things in hand
feet on desk
subsidized cell-phones

"BAD" WHEN OBAMA DID IT:

Corporate welfare
NSA
TSA
DHS
deficits
stimulus
bombing
medicare part D
golfing
hugging Saudi oilers
saluting with things in hand
feet on desk
subsidized cell-phones

Comment: Combo tech (Score 1) 174

by Tablizer (#49794909) Attached to: Why Detecting Drones Is a Tough Gig

What about a combination of image detection and echo-location? Image recognition and/or regular sound detection would identify candidate objects, and narrowly-focused echo location would then scrutinize the candidates further.

And so what if you take out a few birds accidentally? Just place a KFC nearby to handle such. They'll enjoy the free raw materials.

Comment: Re:Waste of Time & Money (Score 1) 233

there are also multitude of valuable scientific experiments that are done on ISS

The science-per-dollar in such ISS experiments has been very poor, considering the total cost of ISS and life-support and maintenance. 100 billion US dollars can buy a hell of a lot of R&D otherwise.

all the Moon missions brought back precious information about its geology. If we could make a self-sufficient base on the Moon and even send a single geologist there they will bring more data then all probes that we sent there to date.

I'm skeptical of that claim. One generally does not know what one is looking at until it's taken back to a lab. And robotic sniffers can do more preliminary analysis than an on-site human geologist per dollar. Robots (multi-spectral cameras) can "see more colors" in a sense. Human eyesight is limited. And we'd have more rocks/soil from more sites if we had sent robots under the same costs.

Comment: Technology Race, not Space Race (Score 1) 233

Our current gap is not really in space-specific technology. An "AI race" and/or 3D-printer/replicator-race would probably better serve the goal of living in space than a "space race" that only focuses on space-specific technology. We should focus on the bottlenecks, and those bottlenecks so far appear to NOT be space-specific.

Think of how difficult it would be to do space exploration in general without compact computers. Computer technology is not space-specific, but computer technology miniaturization happened to be a giant enabler of space exploration. Dumping tons of money into ONLY space-related stuff would not have been nearly as beneficial (being we've mostly plateaued on the mechanical and chem rocket side of things since the late 1950's.)

Similarly, AI and/or flexible manufacturing automation appear to be areas that help in other industries AND space exploration/colonization. Let's try to launch two birds with one rocket.

+ - Sourceforge staff takes over a user's account and wraps their software installer-> 9

Submitted by Anonymous Coward
An anonymous reader writes: Sourceforge staff took over the account of the GIMP-for-Windows maintainer claiming it was abandoned and used this opportunity to wrap the installer in crapware. Quoting Ars:

SourceForge, the code repository site owned by Slashdot Media, has apparently seized control of the account hosting GIMP for Windows on the service, according to e-mails and discussions amongst members of the GIMP community—locking out GIMP's lead Windows developer. And now anyone downloading the Windows version of the open source image editing tool from SourceForge gets the software wrapped in an installer replete with advertisements.


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