Forgot your password?

Comment: Re:USB DACs (Score 1) 502

Personally, I use built-in audio. It really IS good enough for most purposes - I have never been dissatisfied with the quality of my laptop DAC.

My original point was that cheap USB audio (those under $10) are crap, and most people who just want to improve the sound, and CAN tell the difference, don't need the fancy DSP stuff.

I want to Sweetwater's web site. They have a bunch of brands of USB audio interfaces in the $100 range from such brands as Alesis, PreSonus, Yamaha, and M-Audio. Behringer even makes $30 ones, but reviews are mixed. Still, if you need line-in on a laptop, that is the cheapest way. If you ARE into sound and music, you can get even mixers with audio interfaces built-in. Alesis even makes some rather nice studio monitors (speakers) with a USB interface.

Comment: Re:Creepy (Score 1) 188

by harrkev (#47436269) Attached to: DARPA Successfully Demonstrates Self-Guiding Bullets

I don't think the materials science is there to deal with forming/deforming a projectile on the order of 300,000 rpm (presuming a 1:7 twist & 3,000 fps).

Piezo actuators should have no problems working at up high tens of KHz, and even up in the hundreds. Peizo elements are used in tweeters, where they have to react up to at least 20 KHz, in the right range for this project. Piezos do not have much distance that they can travel, but at that speed, you might not need much distance. All you really need is a little paddle that can stick out an slow the bullet down on one side.

Comment: Re:Alternate use for this technology (Score 1) 188

by harrkev (#47436233) Attached to: DARPA Successfully Demonstrates Self-Guiding Bullets

And here's a clue for you. NO one over there wants peace at all, ever.

Sorry, but many Muslims are taught to hate Jews from a very young age:

There are other examples, but this is the most famous one that I could think of.

From what I understand (and I know many American Jews who have visited Israel), the Jews pretty much just want to be left alone.

Comment: Re:Creepy (Score 2) 188

by harrkev (#47434677) Attached to: DARPA Successfully Demonstrates Self-Guiding Bullets

You got it. Lasers are cheap... electronics are cheap... batteries are cheap... spoofing is cheap.

Really, as an engineer, I can imagine two ways for this thing to work, and it depends on if the projectile spins. Typically, bullets spin so that they act as gyroscopes -- always pointing the same direction (YouTube has videos of guys firing pistols into ice -- ice stops bullet which just sits there and spins like a top).

If the projectile spins, you can, in theory, guide it with a single fin that can extend or retract. You could not use a standard camera as such, because you are spinning wildly. Assume 2000 FPS bullets -- if you want to shoot a mile, you need at least this much. Also assume a 1-in-12 twist (real twists are in the range of 1-in-7 to 1-in-14, depending on shape and weights of bullet). That means that the bullet is spinning with a approximate rotation of 2 KHz. I doubt that you could have an effective regular camera spinning like that and still work. A better way would be to have a linear sensor (a line camera) that looks forward and to the side. This could operate. When you see a bright stop, see how far it is from the center. More off-center = kick your fin a bit more. This is simple and straightforward. However, since the bullet is spinning and you do not know when the camera will cross the laser, you probably need to keep the laser on full time. This is probably the easiest and cheapest way to accomplish this, but should be easily spoofed. You could maybe put a crypto on the laser signal by changing the intensity of the signal without turning it off, but it would have to be a much lower frequency than 2 KHz because that is your effective sample rate. If you assume 500 Hz signal (four-times oversampling), you would only get about 500 bits of data before you hit your target (assuming a target 2000 feet away). Is that enough to actually apply crypto? I am not sure...

On the other hand, if the bullet is NOT spinning, you can use a regular camera and regular fins to control it. In that case, it is entirely reasonable to embed some sort of cryptographic modulation on the signal. In any case, the existence of a 2-D sensor makes the bullet more expensive, and increases the amount of processing that needs to be done. It should, however, be more feasible to put crypto, but at greater cost.

Comment: Re:Alternate use for this technology (Score 3, Insightful) 188

by harrkev (#47434367) Attached to: DARPA Successfully Demonstrates Self-Guiding Bullets

I don't get the US. I mean, by now you should have noticed that the bigger and more complicated the technology, the more you play into your opponent's hands. First of all, you're using high tech weapons in a low tech war. You can't really fire any round anymore that doesn't cost you more than what your target cost your enemy.

Off topic, I admit, but this reminds me of the current Isreal/Hamaas conflict. Just launch simple, dumb, and cheap unguided rockets from the Gaza Strip. Isreal has an "Iron Dome" defense system that is supposedly pretty effective at stopping them -- at $1,000,000 per shot. Great way to bankrupt an enemy...

Comment: Re:Creepy (Score 1, Interesting) 188

by harrkev (#47434329) Attached to: DARPA Successfully Demonstrates Self-Guiding Bullets

Actually, this should not be scary at all! You just need to figure out the frequency and modulation of the laser used. Then, just make sure that you have such a laser pointed at the guy beside you. You are suddenly safe from snipers! Just make sure that you do not like the guy beside you.

Seriously, the only way this could be spoof-proof is to modulate the laser with some type of crypto.

Comment: Re:Why 80% (Score 1) 278

by harrkev (#47433621) Attached to: William Binney: NSA Records and Stores 80% of All US Audio Calls

Hey, Obama promised "Hope and Change." Isn't that what we have here? Admittedly, Bush started this -- probably. Or maybe he inherited the seeds from Clinton or earlier -- who knows how far back this trail goes? But Obama has had almost 6 years to fix things. Instead, under his watch, things have gotten worse.

In Obama's defense, I do not know if Romney would have done things any differently, but I suspect we would probably still be here even if he had won.

Comment: Re:USB DACs (Score 5, Interesting) 502

A USB audio interface also lies outside the electrically noisy interior of a PC chassis.

Strong caution with USB audio. There is a metric buttload of cheap USB adapters, While they technically work, they typically lack analog filtering that gets rid of higher harmonics. If you look at the output on an oscilloscope, instead of a smooth wave, you see the actual steps. Better audio hardware should have filters to smooth this stuff out.

Another MAJOR thing is inducing noise into the output. This is not just for USB cards, but all audio solutions. You need some pretty good filtering between the digital and analog power domains -- yet another area where cheap sound can skimp. Hey, let's shave $0.05 off by dropping this capacitor and inductor!

The original article really touches on two separate areas:
1) Audio processing
2) Higher quality audio circuitry

SoundBlaster (and other gaming-oriented cards) typically do both. However, do you really NEED both? The audio processing stuff is supposed to provide an API that games can use to make thing sound more realistic, or offload audio processing from software to hardware, or both. It can typically decode various dolby flavors, and do some other fancy DSP-ish type stuff. Do you really NEED all of that? If so, then maybe a gaming card is for you.

However, what if you want the best sound possible, the lowest noise possible, and don't really game or use the various audio enhancements? You just want a plain-vanilla sound card, but with the highest quality audio. Where to do? Skip the computer store, but go to your local MUSIC store (not the ones that sell CD's, the ones that sell GUITARS). Those cards skip all of the DSP bells and whistles, but have the best-quality DACs and filtering that you can find. You can find some really good USB solutions that will blow on-board audio out of the water for about $100 or so. Of course, you can go crazy and spend $500 or more if you want. If it is good enough for a music producer to use in a studio (who makes his or her living off of the sound), it is probably good enough for YOUR music and movies.

Comment: Re:Unions. (Score 2) 308

by harrkev (#47300811) Attached to: Interviews: Ask Lawrence Lessig About His Mayday PAC

In union there is strength, a lesson the geek never seems to learn. How else do you suppose a day laborer can out-match the billionaire in politics?

Yes, and "union" is nearly as useful as "struct."

Geek humor aside, I am not actually against unions, but I am against making union membership mandatory. In an ideal world, labor vs. management would be a perfect balance. However, bad things happen when one side gets more power over the other. If management is too powerful, poor working conditions and poor wages may result. If unions become too powerful, then the actual competitiveness of the company can be impacted.

True story:

I used to work for a company who is currently known for making a cell phone spy tower named after a flat marine animal. This was well over a decade ago. I had helped design an electronic module used to help test a fighter aircraft. I debugged this card. I touched it, hooked it up to test equipment, had test wires soldered to it, and had an intimate understanding of how it functioned.

Fast forward to when the cards are debugged, so I help deliver this stuff to the customer (big airplane company in Seattle). The technicians were all unionized, which is fine. However, as a part of the union contract, the engineers were not even allowed to TOUCH the equipment. So, I handled this stuff extensively back in Florida, but suddenly I am not allowed to even plug in a cable in Washington. This means that working extra hours to get the job done was NOT an option, since the tech was not approved for overtime.

Sorry, but that SUCKED! Tech deserve to be paid fairly, and they are cheaper than engineers, so it makes sense to use them when they can do the job. But, to say that engineers cannot even touch the equipment that they design is completely asinine, and it means that even if the test setup only needs to be changed every hour or two, the company still needed to pay a technician to be there (extra money), or you have to wait for one to show up (slowing down testing). That is the kind of crap that leaves a bad taste in my mouth when it comes to unions. Fair pay and benefits are one thing. Aggressively protecting your job function to the detriment of the company is another.

Should I even mention the union rules that I have broken by moving my own computer and changing the height of my own cube tables? I am sure that I am going to hell for that one.

Comment: Unions. (Score 5, Insightful) 308

by harrkev (#47298383) Attached to: Interviews: Ask Lawrence Lessig About His Mayday PAC

I was just wondering if you were also concerned about money from unions? To me, a millionaire donating is own money is somehow less problematic than unions taking money from their members to donate. Keep in mind that in many states, union membership is required in order to get the job. Therefore, many union members may find their money being used to support candidates that they do not support.

Comment: Re:This will hugely backfire... (Score 2) 422

by harrkev (#47232053) Attached to: GOP Voters To Be Targeted By Data Scientists

I agree with this completely. I am a rather moderate conservative. And I am against illegal immigration.

Hypothetical question. You are the ruler of a country and you want to have more citizens. Who do you choose to offer citizenship to:

1) Person who goes to an embassy, fills out the required paperwork, and tried to do things the right way.

2) Person who decides that they want in, and ignores the law and smuggles themselves in, making their first act in the country breaking the law.

To me, it seem that #1 has already proven that they can obey the law, while #2 has already proven that they do not mind breaking it.

I must admit that I do have a lot of sympathy for youths who were brought over here with their parents. They did not have much choice in the matter. If there is anyone deserving of amnesty, it is this class. However, the parents should return to where they came from, and fill out the proper paperwork to return here.

egrep patterns are full regular expressions; it uses a fast deterministic algorithm that sometimes needs exponential space. -- unix manuals