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Semi-geeks will want to see what's under the covers at PlayStation1 and PlayStation2

Semi-geeks will want to see what's under the covers at PlayStation1 and PlayStation2

All about Plutonium-239 used in nuclear bombs such as Little Boy.

Ubiquitous networking is interesting, too.

Banner Ads explained and what they cost.

Cable Modem users need to learn about firewalls if the cable guy doesn't tell them!

Cable Modem users need to learn about firewalls if the cable guy doesn't tell them!

Cable Modem users need to learn about firewalls if the cable guy doesn't tell them!

Landfills must be getting all kinds of junk!

Here's how the ISS really works, and some day there will be space tourists, robonauts and inflatable spacecraft.

Here's how the ISS really works, and some day there will be space tourists, robonauts and inflatable spacecraft.

Here's how the ISS really works, and some day there will be space tourists, robonauts and inflatable spacecraft.

Here's how the ISS really works, and some day there will be space tourists, robonauts and inflatable spacecraft.

I'm still looking for a way to use Scroll Lock on my regular QWERTY (designed in 1874!) keyboard!

I'm still looking for a way to use Scroll Lock on my regular QWERTY (designed in 1874!) keyboard!

Interested in wormholes?

Mars Explained! And, there are those that will terraform Mars.

Mars Explained! And, there are those that will terraform Mars.

Here's how the Sony PS2 works, with inside photos.

VDSL should be providing a solution to this problem as soon as the standards are figured out. See how it compares to other DSL standards here.

VDSL should be providing a solution to this problem as soon as the standards are figured out. See how it compares to other DSL standards here.

What is Linux, and why is it so popular?

There hasn't been much press (needling?) lately about the FBI reading of e-mail for some reason. Maybe they have enough media coverage over the delayed lethal injection!

There hasn't been much press (needling?) lately about the FBI reading of e-mail for some reason. Maybe they have enough media coverage over the delayed lethal injection!

Actually, this isn't right. The general scheme is to use an earth return to the power plant. Even if there is a conductor running as a return it shouldn't be carrying any current. You can demonstrate how this works pretty easily with a cheap 2 prong extension cord and a lightbulb.

• Cut the extension cord so that you have a length of cord attached to the end that plugs into the wall. You may discard the end which you'd plug lamps into.
• Cut the wider prong off of the plug end.
• Remove the side of the cord associated with the removed prong.
• Strip a small amount of the insulation from the end of the remaining wire.
• solder this to the threaded part of a lightbulb.
• Plug your modified plug into the wall and touch the base of the bulb to a faucet or other grounded metal object.
• If the bulb doesn't light, turn the plug over and try again.
• BE VERY CAREFUL NOT TO TOUCH THE SHINY METAL PARTS WHEN PLUGGED IN. IT WILL HURT A LOT.

Actually, this isn't right. The general scheme is to use an earth return to the power plant. Even if there is a conductor running as a return it shouldn't be carrying any current. You can demonstrate how this works pretty easily with a cheap 2 prong extension cord and a lightbulb.

• Cut the extension cord so that you have a length of cord attached to the end that plugs into the wall. You may discard the end which you'd plug lamps into.
• Cut the wider prong off of the plug end.
• Remove the side of the cord associated with the removed prong.
• Strip a small amount of the insulation from the end of the remaining wire.
• solder this to the threaded part of a lightbulb.
• Plug your modified plug into the wall and touch the base of the bulb to a faucet or other grounded metal object.
• If the bulb doesn't light, turn the plug over and try again.
• BE VERY CAREFUL NOT TO TOUCH THE SHINY METAL PARTS WHEN PLUGGED IN. IT WILL HURT A LOT.

[Article] Atoms are bombarded by electrons and other minute projectiles, electrically excited in this way and made to glow.

Isn't that a reasonable if simplified description of how fluorescent and neon lights work?

[Article] Jane Dobson throws soiled "linen" in the incinerator

Incinerators can be quite clean if the temperature is high enough and sufficient pollution-control technology is in place. Here's one (not particularly great) example.

[Guppy06] How could anybody that's seen what a V-2 could do in WWII not believe that it would be possible to get to the moon by the end of the century?

It's one thing to launch a missile ballistically, another thing to get into orbit or beyond. Remember that Sputnik wasn't until about 1957 (?), and I'm pretty sure I remember having read that in the 1950s there was still significant skepticism in the scientific community that it would ever be possible to reach the moon.

[Article] Instead of taking electrocardiographs, doctors place heart patients in front of a fluoroscopic screen, turn on the X-rays and then, with the aid of a photoelectric cell, examine every section of the heart

Slightly wrong in detail, but right in principle. I had something like this done a few years back, but with my lungs rather than my heart. I don't remember the name of the procedure, but I had to breathe some mixture infused with a radioactive tracer while laying inside this scanning device that detected the radiation and displayed the results on a CRT in real time. I have to say it was pretty cool to be able to actually see my lungs expand and contract as I breathed. Not X-rays, but otherwise very similar, and I'm pretty sure the same technique can be used with radioactive tracers in the blood (angiography or something like that?). Echocardiograms (and prenatal ultrasound) are also in the same, uh, vein, though again the details are a bit different.

First of all, even without human interference, it conducts heat, electricity, and sound

Heat, yes. Sound, yes. Radio? yes. Electricity? I don't think that having air constantly conducting electricity is a good thing, but I suppose lightning does fit under that bill, but not in the constant sense that you're referring to, unless I'm missing something

If a sub sends out, say, a bleep at 440 mHz, and receives one back from a sub 50 yards away, if the signals were fired simultaneously, both subs will think that they're 100 yards apart.

You got it backwards. If 2 subs simultaneously send out a sonar ping, they will receive the other one in 1/2 the time expected, and therefore think they are 25m apart (1/2x), not 100m (2x).

But think of an ocean filled with five billion submarines, each one sending out sonic vibrations

You're not going to have everyone using the same frequency, and besides, sonar was designed for casual use. If we had 5 billion subs, then we'd be using something a lot more sophisticated.

But how many ways can water vibrate?

You're not looking at things correctly. You don't need to simply assign everyone a different frequency. Think about how modems work. Think about our wonderful 300 baud modems 20 years ago, and now we have 56K packed into a tiny little 8khz of bandwidth, and that's low for that size of bandwidth because of the unperfectness of the phone network! For another example, take 1 freqency and randomly pulse it. I'm not entirely sure of how signals work underwater as well, but I'd imagive that it's not much different than through air. So send a "digital" sonar pulse with a unique ID attached. If you receive one that isn't yours, ... Just like how a network works. There are a zillion ways to pack a lot of different data and signals into a single band.

And can the same cubic inch of water really carry a million transmissions with a million different frequencies and vectors?

Radio waves travel through substance. For that matter, air is not much different than water. They're both 'fluid', one is just a lot more dense than the other. For this matter, you should be able to pack just about the same amount of information through water as you can through air. I'm not an expert, but that only makes sense to me.

What are the possible effects of completely saturating the air with information?

I think we're far from that point, and one thing you're forgetting is that we evolved being bathed in radio waves. The more hazerdous stuff was blocked by our wonderful atmosphere, but radio has always been around. There is no apparent large health risks for the amounts that are being broadcast, at the powers that they are being broadcast at. I think as technology progresses (as it has already), we will be able to pack more and more information into less and less power and bandwidth in the air, and since there's just so much of it, I don't think this is a problem we'll have to face any time soon.

Have a look at the water rocket page and a very nice page about the rocket equations. There is also a good page on howstuffworks

I've seen a whole pile of posts and people thinking that you can "wallpaper" your room or put it on your screen. Think for a second about how sound is made from speakers (or anything for that matter): by vibrations. If things vibrate, it means that they cannot be attached directly to anything except at the edges. You cannot "wallpaper" your room because all of the vibrations would be absorbed by the wall. You could however hang a sheet of this slightly away from the wall, thus giving it room to vibrate. The same thing would happen with a TV screen or your computer monitor. I don't know about you, but the thought of the glass of my screen vibrating at 12,000+ Hz as someone hits the high notes doesn't sound like a very bright idea.

Also, I have here with me a set of Monsoon MM1000s, which are flat panel speakers. Compared to my ($1400, not the best but good IMHO) stereo system at home they sound like crap, however I'm currently in France and I wasn't going to bring my huge towers with me. The flat panels are great for portibility, and considering their size they're really good sounding too. The problem is that you still need an amp for all of this, and the flat panels cannot produce low notes very well at all, so you'll also need a subwoofer.

In any case, speaking as a pseudo-audiophile, in my experience real speakers are still FAR ahead in the game when it comes to raw sound quality. If you want something easy to hook up to your TV or computer to play quake or listen to MP3s, then you can get by on something like this. However if you want quality then you still have to use conventional speakers, and I can't see that changing any time soon, but then again, what do I know?


I saw 21 U.S.Marines, in full dress, with rifles, fire a gun salute to the outgoing president, and every last one of them missed!

I've seen a whole pile of posts and people thinking that you can "wallpaper" your room or put it on your screen. Think for a second about how sound is made from speakers (or anything for that matter): by vibrations. If things vibrate, it means that they cannot be attached directly to anything except at the edges. You cannot "wallpaper" your room because all of the vibrations would be absorbed by the wall. You could however hang a sheet of this slightly away from the wall, thus giving it room to vibrate. The same thing would happen with a TV screen or your computer monitor. I don't know about you, but the thought of the glass of my screen vibrating at 12,000+ Hz as someone hits the high notes doesn't sound like a very bright idea.

Also, I have here with me a set of Monsoon MM1000s, which are flat panel speakers. Compared to my ($1400, not the best but good IMHO) stereo system at home they sound like crap, however I'm currently in France and I wasn't going to bring my huge towers with me. The flat panels are great for portibility, and considering their size they're really good sounding too. The problem is that you still need an amp for all of this, and the flat panels cannot produce low notes very well at all, so you'll also need a subwoofer.

In any case, speaking as a pseudo-audiophile, in my experience real speakers are still FAR ahead in the game when it comes to raw sound quality. If you want something easy to hook up to your TV or computer to play quake or listen to MP3s, then you can get by on something like this. However if you want quality then you still have to use conventional speakers, and I can't see that changing any time soon, but then again, what do I know?


I saw 21 U.S.Marines, in full dress, with rifles, fire a gun salute to the outgoing president, and every last one of them missed!

How Stuff Works has a some information on how self-winding watches work. From the article, the amount of energy generated would seem to be enough to keep the watch running plus a little more-- "enough energy to keep the watch going for about a day and a half if you leave it on your dresser".

I wonder how this sort of level of power is comparable to the triple-As in my Palm...

Streamripper

Streamripper

How Encryption Works explains with drawings and an animation how public-key and symmetric-key systems, as well as hash algorithms really work.
"Look for the "s" after "http" in the address whenever you are about to enter sensitive information, such as a credit card number, into a form on a Web site."

Let me clear it up... :-)

How a diesel engine works.
How a gasoline engine works.
Is Diesel really cheaper than regular gasoline?
What is the difference between various crude oils?
And, since I saw a mention about it in another thread here:
What is octane?

Probably a little bit basic, but an easy read, and should give you an easy to remember understanding of the items in question.

Let me clear it up... :-)

How a diesel engine works.
How a gasoline engine works.
Is Diesel really cheaper than regular gasoline?
What is the difference between various crude oils?
And, since I saw a mention about it in another thread here:
What is octane?

Probably a little bit basic, but an easy read, and should give you an easy to remember understanding of the items in question.

Let me clear it up... :-)

How a diesel engine works.
How a gasoline engine works.
Is Diesel really cheaper than regular gasoline?
What is the difference between various crude oils?
And, since I saw a mention about it in another thread here:
What is octane?

Probably a little bit basic, but an easy read, and should give you an easy to remember understanding of the items in question.

Let me clear it up... :-)

How a diesel engine works.
How a gasoline engine works.
Is Diesel really cheaper than regular gasoline?
What is the difference between various crude oils?
And, since I saw a mention about it in another thread here:
What is octane?

Probably a little bit basic, but an easy read, and should give you an easy to remember understanding of the items in question.

Let me clear it up... :-)

How a diesel engine works.
How a gasoline engine works.
Is Diesel really cheaper than regular gasoline?
What is the difference between various crude oils?
And, since I saw a mention about it in another thread here:
What is octane?

Probably a little bit basic, but an easy read, and should give you an easy to remember understanding of the items in question.

Ants are seriously smaller than the wavelength of your microwave and hence are pretty much unaffected by it- ant heaps can actually live in a working microwave!

Microwave ovens work by exciting molecular bonds at their resonant requencies. Notably, they pump energy into the O-H bonds in water molecules. Thus, anything containing water will be heated in a microwave oven. Ants contain water, of course...so the inside of a functioning microwave would not be a healthy place for them.

However, it should be noted that the distribution of microwave energy density inside an oven is not uniform. Designers try to focus energy in the lower-central volume, where food is most likely to be placed. What's more, the presence of food will absorb energy which might otherwise reach other parts of the oven. Therefore, ants might be able to live around the edges of the oven chamber without getting boiled internally. But this has nothing to do with their size.

--

"The good thing about Alzheimer's is that you can hide your own Easter eggs."

That's too bad Indrema is having problems. Anyways, a short description of Indrema's console is available at HowStuffWorks.com, the most interesting section being Why Linux?. The open source/Linux community already has had it's fair share of failures (Mozilla, et. al.). Unfortuntly, if Indrema fails there is a slight possibility of the Real World(TM)(R)(C) ignoring free software in general for a few decades -- I personally hope they succeed.

That's too bad Indrema is having problems. Anyways, a short description of Indrema's console is available at HowStuffWorks.com, the most interesting section being Why Linux?. The open source/Linux community already has had it's fair share of failures (Mozilla, et. al.). Unfortuntly, if Indrema fails there is a slight possibility of the Real World(TM)(R)(C) ignoring free software in general for a few decades -- I personally hope they succeed.

I think that information, along with the comment about holding 90% of the handheld market was pulled from the How Stuff Works link. On that page they're referring to this being the first horizonal gameboy design...

yeah. confused me at first...

It's mentioned on the second page of the HowThingsWork article. Apparently the battery (chemistry unspecified) slips over the end of the phone after the primary assembly is complete.

--

Altschul, talking on her cell phone, lost her connection and became so angry that she wanted to heave the device out the window. She didn't because the phone was too expensive.

Can we have paper laptops for the same, um, killer app?

http://www.howstuffworks.com/disposable-cell-phone .htm?printable=1

Qoute:

The disposable cell phone is just the first of more than 30 disposable electronic devices that Altschul says her company is preparing. In 2002, we may see disposable laptops

Emphasis theirs.

There's an interesting (and simple) explanation of the technology behind this at HowStuffWorks.com:
http://www.howstuffworks.com/disposable-cell-phone .htm

There's an interesting (and simple) explanation of the technology behind this at HowStuffWorks.com:
http://www.howstuffworks.com/disposable-cell-phone .htm

BTW: There's a solution to the Chicken and Egg problem.
--