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Comment: Re:Unclear who this hurts (Score 1) 56

by ScentCone (#49800331) Attached to: Feds Bust a Dark-Web Counterfeit Coupon Kingpin

Bullshit. Unless you can point to real evidence this is true, you're just guessing.

What? How do you think that coupons actually work, anyway?

1) You present a coupon, and you pay less cash at the point of sale than you otherwise would have. This is not a mystery. It's the whole point. If it's the retailer's own coupon, then they are basically putting the item on sale in exchange for having a trackable form of marketing. If it's a manufacturer's coupon, then the retailer is participating in a mechanism wherein the manufacturer and retailer have worked out a back-channel compensation scheme for the retailer having collected less cash during the transaction. This is also not a mystery.

2) When you present the retailer with a bogus retailer coupon, you're getting a discount that's disconnected from one of the key reasons they issued the coupon in the first place: to understand which marketing methods are the most constructive. When you present the retailer with a bogus manufacturer's coupon, one of two things happens: the retailer eats the loss, or the manufacturer does. Again, why are you acting like this is some strange unknown? Or, are you just hoping that someone there's a third magical possibility that makes it just fine to rip off businesses with fake coupons? Yeah, I thought so.

Comment: Re:Unclear who this hurts (Score 1) 56

by ScentCone (#49800287) Attached to: Feds Bust a Dark-Web Counterfeit Coupon Kingpin

Is short, this "informative" post is nothing but a guess.

What you mean is that you have no idea how retail operations and promotional marketing work, but you vaguely want it to be true that ripping off stuff through the use of bogus discount coupons is a "victimless crime" blah blah blah, so you're going to pretend that basic information is unknowable, as moral cover. Hint: you're not as clever as you think you are.

Comment: Re:The things pump out plenty of RF. (Score 1) 213

by ScentCone (#49798591) Attached to: Why Detecting Drones Is a Tough Gig

I think there should be a no carrier in there somewhere.

Which wouldn't matter a bit if the machine is flying waypoints using its own internal flight controller. That's how mine work: you inform the machine of the flight plan using a ground station, and then it does off and does its thing, whether or not you can talk to it along the way. Loss of, say, Verizon's signal wouldn't make a bit of difference.

Comment: Re:Unclear who this hurts (Score 3, Informative) 56

by ScentCone (#49798125) Attached to: Feds Bust a Dark-Web Counterfeit Coupon Kingpin
Both. The retailer takes on the overhead costs of handling the coupon. They are then collecting less money at the register, but never seeing the expected promotional kick-in from the defrauded manufacturer ... unless the manufacturer wants to continue to provide the retailer with promotional money for fake promos that never actually happened. All sorts of back-and-forth with the accounting, tax implications, distorted reporting - just bad for everyone all the way around.

Comment: Re:Even if you go DC, stay at 120V (Score 1) 528

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) 528

(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) 528

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:Seeking Technical Solution to Social Problem? (Score 1) 213

by ScentCone (#49795655) Attached to: Why Detecting Drones Is a Tough Gig

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) 213

by ScentCone (#49795617) Attached to: Why Detecting Drones Is a Tough Gig

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:WTF is the matter with you people? (Score 1) 230

by Just Some Guy (#49792747) Attached to: In a 5-star rating scheme, the new Mad Max film ...

it should not be mad max, since NONE of the ORIGINAL CAST, CREW, OR MEMBERS IS APART OF THIS NEW PROJECT AND PROBLLY FOR GOOD REASON.

As opposed to the Star Trek 2009 which had Nimoy alone, and in a bit part.

screw mad max, lets cal it what it is, Mad charlez, the rise of estrogen in a post apoplectic world..

Oh, you're one of those guys. OK. Thanks for clarifying; that explains a lot. I'm not a feminist (except in the "women are equal, we should treat them like people" sense), but you'd have to be a major MRA to have any problems with Fury Road. Oh, there was a strong woman character and Max had a peer and an equal. Shock! Horror! [insert eye roll here] If you can't enjoy Furiosa being as fierce of a survivor as Max, then there's something broken in you.

Comment: Re:Even if you go DC, stay at 120V (Score 4, Interesting) 528

(Continuing after brushing the touchpad posted it for me. B-b) ... equipment at that voltage. (Small systems are often 12V due to the availability of 12V appliances.)

But back to inverters:

Current inverter and switching regulator (they're pretty much the same stuff) technology is SO efficient that large PC boards in computing and networking equipment may run the power through as many as THREE DC-DC converters, because you lose less power to heat as losses in the inverters than you would to resistance running it a few inches through a printed circuit board power plane.

So the '"20-40% loss" number seems to me to be utterly bogus.

(Consider this: A Tesla automobile IS AC motors driven by inverters from batteries. A horsepower is almost exactly 750 watts. If they had 20-40% losses in the inverters, how do you keep the car from being on fire after a jackrabbit start? Let alone recover enough power on braking to reuse on acceleration to make a substantial difference?) If ANYBODY knows how to handle inverters it's Tesla. B-) )

Disobedience: The silver lining to the cloud of servitude. -- Ambrose Bierce

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