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Comment: Re:Better get the service manual, then (Score 1) 25

Insightful, really? I think a few mods must've missed a "whoosh" somewhere.

Either that or they haven't seen how modern Haynes books have reinvented themselves given their old business pretty much evaporated once the 90s hit. (Yes, I remember the shelves of Haynes books back in the day and the modern internet has pretty much killed that business.)

Yeah, so it's a bit more complex than just a power supply sequencer and simple "power good" monitor? It's actually recording "telemetry" off its own power supply continuously, then they correlate the data later?

But can they turn off a power supply and take a resistance reading, for example? Or how about varying the voltage while monitoring the current?

In a spacecraft, because it's really difficult to bring it in for service and diagnostics if something goes wrong, you pretty much have to build in all the diagnostics as telemetry. The more information you can gather the better diagnosing you can do - and if you miss one, well, you can't go and probe it later with a multimeter.

So easily measured stuff like voltages and currents of power rails is instrumented because if something goes awry, that's all the data you have. Analog channels are cheap (they're generally multiplexed together) while sending someone to go and measure it for you is pretty expensive, if it's even possible to do.

The power supply inputs (solar panels, RTG, etc) will have current and voltages measured on each input (e.g., each solar array input channel will have voltages and currents monitored, not just the aggregate), the battery current and voltage will be monitored (maybe even on a per-cell basis), the output power rails of the power supply will be monitored, and the input power used by each instrument as well. If an instrument starts drawing significantly more current, you can tell which one it is and see how the rails dip. If the sum of the currents used by the instruments don't match the current the power supply is providing, then you have a short somewhere. If a power rail is off but you're still seeing voltage and even current, you can tell if the switch is bad, or if it's being backfed or a short is carrying power on it. Or if a rail goes out of spec (overvolt or undervolt).

It's unlikely they can turn off a rail and measure it - it's generally not too useful a measurement if you have current and voltage measured every which way.

And yes, there is other telemetry that's possible, including temperature, angle encoders (encoding positions of each servo in an instrument and maybe even the wheels, etc).

Comment: Re:Maintainable... (Score 1) 207

by tlhIngan (#49180623) Attached to: Study: Refactoring Doesn't Improve Code Quality

I'd say it's more "real" than that - personally I'd regard the "optimal refactoring situation" the one where you have a piece of code that originally did one thing, then had years of frankensteinesque new functionality hurriedly bolted on to it until it barely resembles it's original self and is likely to blow up if you look at it wrong. At some point rewriting the code with the complete current functionality, and likely future expansion, in mind is going to make it much clearer and easier to modify further without random bits interfering with each other.

Well, refactoring also is the opportunity to apply previous experience to the new code as well.

When refactoring, you can trim out the fat - the original code may have been written to satisfy features X, Y and Z, but as it evolved, Y and Z were never used, yet its code exists and often has to ve special cased to support real use cases of Y1 and Z3 (Z1/Z2 were old requirements that were obsoleted).

Also, decisions may have been made because the system may have added possibilities for X1, X2 and X3 as they were planned into the requirements, but real business operations deemed there was no practical use case in the end.

So refactoring to current spec simply say you need to support X, Y1 and Z3. But experience has taught you that X is unlikely to ever change, Y was revised so maybe make it possible to revise it should it be necessary, and Z needs to be flexible because it's Z3 now, but past experience shows Z4 and Z5 are likely so that code should be made as adaptable as possible. And maybe redesigned since Z needs the flexibility, while X is static and Y changes are limited.

Comment: Re:Hey Roblimo: Make a "loser edit" autobiography! (Score 2) 82

by mrchaotica (#49179919) Attached to: Technology's Legacy: the 'Loser Edit' Awaits Us All

The job of an editor is NOT to just present stories that go along with the group-think of the day. We have Faux News and their ilk for that. Also, if they edit submissions too much "for clarity" the submitter will complain that's not what they wrote. So what are you going to do?

Well, would it be too much to ask for them to fix the typos and make sure the links work?

Comment: Re:How? Reaction is equal and opposite. (Score 1) 334

The problem is that the response is not proportional because everyone who hears about this and is offended on behalf of the victim can take their little piece of revenge. There is nothing to keep this public shaming reasonable or just.

The problem is idiots who don't realize the internet is not a toy. Trolls do it for the lulz and don't realize that no, they're actually creating a very permanent record of their activities.

People are worried about "government surveillance" because it chills online speech. Guess what? The Internet does that independent of government by having basically a permanent record - what you do today can impact you decades in the future.

So I've got little sympathy for those who don't know how to behave online, because it was instilled on me since the beginning the dated phrase "If you don't want it posted on the New York Times, don't post it online". Adjust it as necessary, but the truth is there - what you do online is NOT private, and is eternally recorded and what you did might end up plastered all over the news.

Troll all you want, but realize that your five minutes of fun is recorded and you may find yourself as the top news story worldwide. If you want to offend, go for it knowing it WILL haunt you forever. This isn't a bathroom wall in some gas station - it's a gigantic unforgetting bathroom wall that the world sees.

Comment: What's the key spacing? (Score 1) 53

by Ungrounded Lightning (#49178401) Attached to: A Versatile and Rugged MIDI Mini-Keyboard (Video)

Is the key spacing the same as a standard piano keyboard? If not, how does it deviate?

Can it, in combination with some particular, commonly-available, MIDI software package(s), be programmed to have the same touch characteristics and sound as a piano, harpsichord, etc.? If so, are the configurtation parameters to produce equivalent performance already available?

Comment: Re:It's not the PC microphone ... (Score 1) 87

by Ungrounded Lightning (#49177877) Attached to: Ask Slashdot: Wireless Microphone For Stand-up Meetings?

Or bypass the problem completely by using a USB microphone. These digitize the audio right next to the microphone proper, with everything floating at the same voltage so nothing substantial is picked up betwen the air pressure sensor and the A-D converter.

Bluetooth headsets work great for this, too. Most current generation laptops already have the bluetooth central-role radio onboard. Or get a cheap low-profile bluetooth dongle.

Comment: It's not the PC microphone ... (Score 1) 87

by Ungrounded Lightning (#49177857) Attached to: Ask Slashdot: Wireless Microphone For Stand-up Meetings?

4. PC/laptop microphones suck. I don't know why no one bothers to test them to the same level as your average cheap dumbphone speakerphone. They pick up all kinds of system electrical noise, ...

The problem usually isn't the microphone. It's the way it's wired (per the standard) and the way the desktop/laptop is powered.

PC microphones are wired UNbalanced: They have a signal and a ground wire, rather than the + and - signal wires and everything-but-desired-signal cancelation of the balanced wiring setups typical of professional microphones.

Laptops typically use power supplies that are not grounded, so they don't require a three-prong outlet. This usually ends up with the stray capacatance to BOTH sides of the line wiring capacitively coupling equally to the laptop "ground". That means the "ground" of the laptop is at half the line voltage - about 60 volts of AC (a rotten approximation of a sine wave plus lots of other junk it picked up at an assortment of frequencies). The capacitance is substantial - not enough to shock you if you touch the laptop and ground, but enough to feel a buzz if you rub your hand lightly across a "grounded" metallic part of the device.

Plug in the unblanced microphone and hold it, put the headset on your head, or just leave it sitting on the table. The "ground" is at 60V and you are driving maybe a couple MA of it down the shield wire. The voltage drop of that current (along with any other pickup) adds straight onto your audio input. The best microphone in the world will perform horribly if hooked up this way.

Try this: Unplug the laptop and let it run on battery. Notice how almost all of the noise disappears. You can also get rid of most of the noise by tying a decent ground onto the laptop. (Unfortunately, many meetings last longer than the laptop batteries...)

Plug in a VGA monitor with a three-prog power plug, which grounds the case of the laptop via the shield and the two hold-in screwd. I've done that without actually hooking up the monitor (which would have disabled my laptop screen) by adding a couple of the nuts scavenged from another DB connector as conductive spacers so the actual signal pins are not quite into the plug. And done this on a docking station, so the laptop headset was quieted when the laptop was docked, even though I used none of the docking station features except the power input.

Make a second cable with a three-prong plug to bring a ground up to the laptop. Green wire from the third pin to a screw into or clip onto such a chassis ground point.

Or bypass the problem completely by using a USB microphone. These digitize the audio right next to the microphone proper, with everything floating at the same voltage so nothing substantial is picked up betwen the air pressure sensor and the A-D converter.

Comment: Re:Parody (Score 1) 236

by cpt kangarooski (#49177671) Attached to: Gritty 'Power Rangers' Short Is Not Fair Use

And time shifting doesn't use just one. Time shifting monetized (when done by a company) is almost always not fair use. Tivo is the only one that survived legal challenges.

Time shifting is typically something that the end-user does. Tivo, like Sony before it (The original time shifting lawsuit was against Sony for their Betamax), merely makes the machine. So long as there is at least a potential lawful use for the recording function of the machine, they can go on making them. The Supreme Court found that at least some time shifting would be fair, and that was enough.

Space shifting is another example, the original case was against Diamond for their Rio MP3 players, but Apple's iPod relied on it, as did basically everyone else.

But it meets more than just one criteria. It's non-commercial.

No, the purpose of the use for time shifting, while not precisely commercial, is to simply use the work in the way that an ordinary user, who did not time shift, would use it. It's not strongly against fair use, but it certainly doesn't weigh for it in the way that an educational or transformative use would. At best it is a wash.

Comment: Re:Parody (Score 2) 236

by cpt kangarooski (#49177639) Attached to: Gritty 'Power Rangers' Short Is Not Fair Use

I don't think the parody exemption for copyrighed works applies to things protected by trademark, which I wouldn't be surprised if the Power Rangers are.

It does.

(Though the question of parodying a mark directly is different from parodying a work which happens to contain a mark. Parodying Star Wars, which includes X-Wings, and the Millennium Falcon, and Lightsabers, and so on is different from parodying the Star Wars logo all by itself)

Also, remember that trademarks are inferior to, and cannot be used as a substitute for, copyrights. And that trademarks themselves are subject to various limitations to allow for certain types of unauthorized use.

Comment: Re:Parody (Score 2) 236

by cpt kangarooski (#49177611) Attached to: Gritty 'Power Rangers' Short Is Not Fair Use

Peter Pan is in the public domain in the US. You can absolutely have Peter Pan promoting drug use ('fairy dust' can be the street name; a side effect might be paranoid hallucinations of ticking crocodiles, etc.), and publish it widely enough to detract from Disney's ability to keep Peter Pan a wholesome character that they can make tons of money off.

Go nuts.

But because people can ignore that -- In fact, I'm confident that there are bad porn versions of Peter Pan floating around -- it doesn't really detract from the original, or from the Disney movies, unless you allow it to. It's up to you, the audience member.

Comment: Re:Parody (Score 2) 236

by cpt kangarooski (#49177593) Attached to: Gritty 'Power Rangers' Short Is Not Fair Use

a parody is allowed to use however much of the original work it wants to.

That's not quite right.

There's no special status for works which are parodies. Some parodies can be fair uses, but not all parodies are. And not all fair uses are parodies, though some fair uses are.

In any case, one factor in determining whether a use is fair or not is how much, and of that how substantial a part, of the original work is used. It's possible to have a fair use that uses all of a work, but also possible to have a use which uses very little of a work, but which is not fair.

While it all depends on the circumstances at hand, a good rule of thumb is to take only so much as you need. If you wanted to make a parody of Star Wars about how Luke waving the lightsaber around in Obi-Wan's house is dangerous, because Luke is a klutz, you could probably use some footage of that scene from the movie. You would have a harder time justifying using the entire movie, but only changing that one scene for the purposes of parody.

Comment: Re:Parody (Score 2) 236

by cpt kangarooski (#49177547) Attached to: Gritty 'Power Rangers' Short Is Not Fair Use

You're allowed to use copyrighted material to parody that specific material, but not to parody something else.

This is the oft-cited parody/satire dichotomy.

No seriously, some people really get into this stuff.

Anyway, it's not a bright line rule or anything, though some people like to pretend that it is. Satire is just as able to be a fair use as a parody can be, and a loss on the third fair use factor does not by itself prevent a use from being a fair use. There are no bright lines in fair use; it's all case-by-case analyses, utterly dependent on the specific facts at issue.

Comment: Re:Parody is protected (Score 1) 236

by cpt kangarooski (#49177525) Attached to: Gritty 'Power Rangers' Short Is Not Fair Use

Parody is protected; satire is not.

That's not really true. There is no hard and fast rule to this effect. Certainly fair use allows for both some parodies (but not all parodies) and some satires (but not all satires).

Courts generally are more likely to find fair use where the use was limited to what was needed, and generally find that satires don't need to use particular works so much as parodies do (because a parody is aimed at the work itself, whereas satires merely employ a work to aim at a different target altogether). But there's nothing in the law that prevents a satire from being a fair use depending on the overall circumstances. It's just a little harder to show.

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