Small Change, and Other Physics Fun

fishy jew writes "Ever want an easy way to make your 'small change' even smaller? Well, Bert Hickman has it - mix a home-brewed machine, 6.5 kiloJoules, and 100,000 Amps of current! On his website, he has descriptions and pictures of his many exploits with large quantities of electricity, notably including shrinking coins, building a Tesla coil, creating Lichtenberg figures (chaotic sculpture), and more! He has extensively outlined the equipment, procedure, and results for each of his experiments, and included many pretty pictures, too. Here are Google caches for when the site gets /.'ed: Main Page, Shrinking Coins, Tesla Coil, and Lichtenberg Figures."

Comments

I own one of these coins... very cool

[Punchinello]

I bought a shrunken Sacagawea Dollar from this site in May, 2003 (around the same time my Slashdot story submission about the site was rejected). The coin is truly amazing to look at and a hit at parties. The details of Sacagawea and the Eagle are perfect, only smaller (although the coin itself has a bit of an uneven surface caused by the rapid shrinking process). I'm happy to see the site finally get the news for nerds treatment it deserves.

There is a cool Popular Science article for more information.

Now go buy some coins to fund Bert's efforts!

Re:I own one of these coins... very cool

[Ralph Wiggam]

That's one way to be a hit at a party. The other way is to bring good drugs. They're both cool.

-B

Re:I own one of these coins... very cool

[ThomasFlip]

They should name these coins after George Bushes fiscal advisors.

Re:I own one of these coins... very cool

[Monkelectric]

Yea I was going to submit it, but all my submissions get cancelled because I suck so I didn't even bother :)

For those who now can't get to the site: These coins are "shrunken" by being placed inside a wooden dowel, the dowel is then wrapped with electrical wire, and a ton of electricity is then discharged into the coil -- the resulting magnetic field deforms the coin (shrinks usually, but not always!), and causes the entire apparatus to explode :) Small shrinkings are done in blast chambers, larger ones have to be burried in a burm. Usually industrial capacitors provide power.

Re:I own one of these coins... very cool

[Merlin42]

Im pretty sure this has been on slashdot several times but I could only find one other:

http://slashdot.org/article.pl?sid=01/02/21/1940 23 4

Re:I own one of these coins... very cool

[vistic]

"The coin is truly amazing to look at and a hit at parties."

What kind of party are those?

Re:I own one of these coins... very cool

[Radish03]

Obviously the type of party slshdotters go to and actually associate with others.

Re:I own one of these coins... very cool

[stuffman64]

Curious, do the coins weigh as much as thier non-shrunken counterparts? I wonder what this does to the structure of the metal... perhaps this process could be used to make ultra-dense objects such as bullets that are much more damaging than regular ones.

Re:I own one of these coins... very cool

[volkris]

Clinton's would be more appropriate...

Re:I own one of these coins... very cool

[Anonymous Coward]

Abd I'm sure Bush giving millions of dollars away in taxcuts to the rich had NOTHING to do with it.

asshole

Re:I own one of these coins... very cool

[noodler]

now i also know why bush never signed the kyoto agreement.,.,

Re:I own one of these coins... very cool

[Anonymous Coward]

Burn!

Re:I own one of these coins... very cool

[zero_offset]

Yes, for the same reason a sheet of aluminum foil weighs the same as that sheet wadded into a ball. You're just increasing the density. The mass is unchanged.

Maybe he should

[Herkum01]

Have redirected some of that current into getting a more powerful network connection.

Shrinking bandwidth

[carcosa30]

Apparently the slashdot effect is a kind of physics fun he didn't account for...

Re:Shrinking bandwidth

[Pumpernickle]

Cheaper, too. Besides, you wouldn't believe the figures the cable for his connection starts making when he gets linked to from /. ^^

Re:Shrinking bandwidth

[Alien54]

Apparently the slashdot effect is a kind of physics fun he didn't account for...

With any luck, he'll be out partying tonight, getting smashed. Then he comes home completely toasted, and has to rebuild the server from the pile of smoke he finds in his server closet.

Hell is working on MS stuff drunk and plasted. You'll never know what will happen [read the comics through to the end]

Re:Shrinking bandwidth

[Anonymous Coward]

"Slashdotted" ... we've acted over the past few years as if it is (1) funny (2) a fact of life (3) some sort of reward

In fact it is none of the above.

OK /., get off your/our collective arses and fix this. If /. doesn't get /.'ed, then why should articles directly referred to?

Ok, mod this down. It is not essential to the topic in question. It is essential to those who create valuable content. Up till now, /. punishes them as much as it recognises them.

All it takes is a little magic (SMOP) to make all links refer to a /. cache, and some poor little content creator in Singapore or Cincinatti won't be destroyed. Get on with it!

Patrick Keogh
(yes I have an account, but I can't bother, patrick@keogh.net.au)

Re:Shrinking bandwidth

[WeblionX]

And I never knew physics existed in such a way to allow for a pile of smoke.

Google Cache?

[ResQuad]

Doesnt do anything, because it doesnt cache the pictures. And thats the largest problems of slashdoting. I think slashdot should try to temp mirror the pages for the first few hours it goes up, if its a small site.

Re:Google Cache?

[Anonymous Coward]

To see check out auctions by him:

Here, Here, Here, And Here

Re:Google Cache?

[La Camiseta]

This is exactly the reason that I think that Slashdot should put up some Freenet mirrors. At least then, when there's a big rush of requests, the little site's servers wouldn't get the big hits, and the bandwidth would distribute itself out like BitTorrent.

Re:Google Cache?

[Jonah Hex]

Check out these two posts on the topic of /.'ing small sites and why /. can't mirror sites, you may find them informative.

Jonah Hex

Re:Google Cache?

[ScrewMaster]

Right, so that Slashdot can Slashdot itself. Recursion, anyone?

Re:Google Cache?

[Anonymous Coward]

I think slashdot should try to temp mirror the pages for the first few hours it goes up, if its a small site.

Well, did it start out as a small site, or did Bert Hickman shrink it?

Re:Google Cache?

[Forgotten]

Not only does it not help, it does harm, since the small site keeps getting hit for the inline images.

There is no real distinction between the slashdot effect and a DDOS; Slashdot should think itself lucky this hasn't come up in the courts yet. It will. This guy does business through his website (selling the fruits of all the electricity). One day someone will be inconvenienced and have no sense of humour about it.

A proper mirror for small sites in an upcoming story is a necessity. Slashdot should already be contacting site owners to warn them before posting a story and knowingly sending them a huge flood of visitors that they may not be able to deal with, so copyright issues could be worked out then. A standard "we'll only mirror it for 24 hours" deal would be fine with most everyone. Some story submitters are already doing this, but it's not their responsibility - it's slashdots.

This problem will eventually result in a lawsuit if it's not addressed. It stopped being funny years ago.

Re:Google Cache?

[foo1752]

I think that Slashdot should put up some Freenet mirrors

Yes, that's a fantasic idea. Then, it would take me all weekend to finally have those pictures of shrunken coins appear in my browser. Thank God for Freenet!

Re:Google Cache?

[general_re]

There is no real distinction between the slashdot effect and a DDOS

Other than the critical distinction of "intent", of course. Suing someone for things that fall under the heading of "shit happens" rarely leads anywhere useful.

Re:Google Cache?

[HD Webdev]

A proper mirror for small sites in an upcoming story is a necessity. Slashdot should already be contacting site owners to warn them before posting a story and knowingly sending them a huge flood of visitors that they may not be able to deal with, so copyright issues could be worked out then. A standard "we'll only mirror it for 24 hours" deal would be fine with most everyone. Some story submitters are already doing this, but it's not their responsibility - it's slashdots.

This problem will eventually result in a lawsuit if it's not addressed. It stopped being funny years ago.

Web sites are put up to be viewed by anyone on the planet who chooses to go there.

Going to court with an accusation of 'I put up a nifty web site and all these slashdot people killed it because it was so popular' will not sit easy with any Judge I have seen.

If Slashdot was such a menace to the internet, web servers would be configured to barf up some small page to http referrers from slashdot.org.

It may seem like a big deal to us from the inside, but from the outside, the total percentage of web sites per YEAR slashdotted comes extremely close to 0%.

Re:Google Cache?

[aardvarkjoe]

No, Taco's "I can't mirror because of copyright" is an excuse, not a reason. There is no good reason why they could not e-mail the webmaster and request permission to put up a temporary mirror. They don't do it because of laziness and because they like the notoriety of the slashdot effect.

Re:Google Cache?

[Lord Kano]

I salute you. You have taken Karma whoredom to a new level. You just got a 5 Score for posting links to your own week-old slashdot posts.

LK

Re:Google Cache?

[BillyBlaze]

I agree. And it wouldn't even need to delay the story: wget the page (but don't publish the copy yet), post the story, email the webmaster. If he tells you to go ahead and relieve his servers, then change the links to point to your copy, otherwise keep them and throw away the local copy you made.

Re:Google Cache?

[Jonah Hex]

Actually I only intended to pass on some info on a subject that interests me as a puter/network tech, so that those who feel likewise can check out this admittedly off-topic subject. My post is short and sweet, links to original insights/info, and does not attempt to disguise the fact that I wrote them; and despite the fact that I posted without my karma bonus I have as little control over what happens once I hit Submit as the next /. ID does...

Jonah Hex

Re:Google Cache?

[jamesh]

I wonder how much the inconvenience cost him vs the number of additional sales he might get from this free advertising...

think about that for a second. How much would an advertising shop charge to guarantee even a 10th of the hits slashdot generated?

I don't know how it would stand up in a court of law anyway. If you put up a web site for people to look at, and something like slashdot says 'Hey everyone, come and have a look at this cool site!', on what basis would a legal or civil case be mounted against slashdot?

btw, I still find it funny :p

Re:Google Cache?

[Slinky Saves the Wor]

Technically, yes, Google cache is in violation of copyright. But then again all proxies anywhere are in violation... So basically you couldn't even surf the said pages, as the bits get copies in transit. Just read some $BIG_CORP Terms of Use and you'll see.

But using common sense should prevail here. If Slashdot directs x thousand people to some site simultaneously, it would be prudent to mirror the entire site. Some people pay for bandwidth. Some people have a bandwidth/transferred bytes limit, if you exceed it and no more pages for you. And so on. I'm sure the mirroring would benefit everyone.

Besides, if Slashdot is so afraid of copyright violations, why are the mirror URLs posted by individuals allowed in the forums...? Let's have automated Slashdot mirroring. How would it be different from what Google is doing?

Re:Google Cache?

[Jim the Bad]

More information on that here.

Re:Google Cache?

[Thing 1]

I agree with your idea about mirroring; I don't think that a lawsuit is doable (which doesn't mean someone won't try it).

One of the problems with mirroring is the site's administrators won't have the increase in hits (and corresponding ad revenue). Perhaps a mirror template could be set up which understands the biggest advertisers' methods so the hits could still be counted by the original site (and a percentage given to the mirror host, to defray some of the costs of mirroring?).

Once the mirror is closed, statistics should be sent back to the site's administrators. And when the mirror is "closed" the mirror URL should still exist, but be redirected to the original site.

Perhaps the mirror could "hijack" the original URL (with the site's permission of course) so the site would send visitors to the mirror. The site would still get a lot of hits and might crumble under that load, but it wouldn't have to send pages and images, just refer the visitor to a different URL which would be 100 bytes or less, most likely.

I would start this project but it's not an itch I need scratched...

Hmm..

[Anonymous Coward]

I wonder how much I'd have to pay for an ad cleverly disguised as a slashdot main story.

Re:Hmm..

[onemorehour]

Great cynicism, but that's not a very profitable venture. How many shrunken coins do you have to sell in order to replace your smoldering heap of a web server?

Re:Hmm..

[ColaMan]

Surprisingly few seeing that, contrary to popular slashdot belief, web servers don't actually burn.

Re:Hmm..

[onemorehour]

I think that, contrary to your belief, slashdot posters don't actually think that webservers burn under load. Instead, they employ hyperbole to make a joke. It's much funnier to imagine a webserver catching on fire than, say, someone dealing with an IIS crash and/or paying for high bandwidth usage.

On a side note, web servers burn at high enough temperatures, just like most things.

Re:Hmm..

[aardvarkjoe]

Surprisingly few seeing that, contrary to popular slashdot belief, web servers don't actually burn.

Oh, yeah? Then what's this?

Re:Hmm..

[penguinboy]

Oh? I beg to differ.

Re:Hmm..

[orkysoft]

Maybe you can shrink that too?

How about shrinking spammers' heads?

Re:Hmm..

[The Wicked Priest]

I once had an Apple II floppy drive literally go up in smoke. Of course that was before the WWW.

Not a record, but...

[pla]

No posts yet, but already slashdotted.

Actually, though, I have seen his page before. really cool toys, but strikes me as something most of us would probably not want to play with.

Worry about the health risks of frequent cell phone use? Doesn't even come close to the RF this sucker puts off. Not to mention ozone and the very real risk of simple death from electrocution...

Re:Not a record, but...

[Anonymous Coward]

That's ok, I saw the pictures year ago when this someone else like this was highlighted on Slashdot. You can find about six sites with people "shrinking" coins. I'd give a link, but you know why I don't.

Electrocution isn't the only danger. These things are explosive.

Re:Not a record, but...

[Anonymous Coward]

I wish I'd remember to proof read more than twice.

Re:Not a record, but...

[The-Dalai-LLama]

From parent post:

but strikes me as something most of us would probably not want to play with.

Which may be why the page's warning takes up as much space as the page's main title.

From story (sort of):

"Ever want an easy way to make your 'small mind' even smaller? ... mix a home-brewed machine, 6.5 kiloJoules, and 100,000 Amps of current!

The Dalai Llama

Who learned at a very young age that stripping the cord from an old clock, plugging the cord into the wall, and touching the bare wires to both sides of a watch battery produces an amazing spectacle that will put one off of any later attempts at producing home-brewed mini-change.

Re:Not a record, but...

[ErichTheWebGuy]

I see he is using IIS. Poor guy. I think if the number of connections > 3 then that irritating microsoft 403.9 page gets spat out. grr

Re:Not a record, but...

[PurpleFloyd]

Why wouldn't I (and many other slashdotters) want to play with equipment like this? To me, the extremely slight risk of cancer caused by short, high-intensity broadband RF pulses is more than offset by the sheer coolness factor of playing with something like this - a little like a geekier form of "extreme sports," perhaps (God knows I already drink enough Mountain Dew).

Even without the coolness factor, though, the risks are still rather slight with some attention to safety.

Electrocution actually isn't much of a risk with many HV devices - most will destroy themselves (or run up against current limiters) far before they output anywhere near the 200-250 mA needed to stop the human heart. While a shock from a tesla coil or other HV device will hurt terribly and pose a risk of burns, it probably won't kill you. Although some devices designed to deliver a high voltage and high current pulse can be extremely dangerous, keeping aware of safety at all times and never using jury-rigged solutions can mean that even a seemingly dangerous activity like playing around with Tesla coils and coincrushers is fairly safe.

As for ozone, all that you have to do to eliminate most risk is to work outside or in a ventilated area, and not stay around areas where arcing has occured. It's certainly not more dangerous than spraypaint, at least in the quantities produced by most amateur experiments. Bottom line: it's reasonably safe and a lot of fun, so why not do it?

Re:Not a record, but...

[ScrewMaster]

Not quite the same thing. The output of a Tesla coil is not in the band that ionizes living tissue (like, say a cell phone or a microwave oven in the 2.4 Ghz. range.) High-powered RF by itself is harmless enough: passes right through you. Generations of HAM operators have sat next to their transmitters with no ill effects.

There is relatively little risk of electrocution from a properly-tuned Tesla coil, although you could easily suffer a nasty RF burn if you're not careful (those take a long time to heal, for some reason.) Skin-effect keeps the current from passing through your body, but if the unit has low-frequency harmonics superposed upon the RF waveform you can get a nasty shock. I've experimented with Tesla coils (many years ago) and could stand there holding a sharp metal rod in one hand drawing a two foot arc to the discharge sphere. Scary as hell but lots of fun.

You are at far greater risk of electrocution from an electrostatic generator. A Van de Graaf or Wimshurst of even moderate size coupled with enough capacitance can kill you in an instant.

Re:Not a record, but...

[Ironsides]

What RF? This is all Electro Magnetism. No radio waves to speak of at all from this stuff. If he built a full size replica of the original tesla coil, that still wouldn't do much to a human. (FYI, I have seen that one in action people. The faraday cage is to protect the computers from rebooting.) About the only thing I would be woried about is my watch going caput. Or my computers rebooting on me.

Re:Not a record, but...

[Anonymous Coward]

Yeah, seriously. I work on an experiment with a 27 MJ superconducting solenoid. (Used for generating a 1.5 T field over a fairly large volume). When the thing quenches, there's a sort of loud WHOOSH as the field energy is rapidly released and the energy of 6.4 kg of TNT is effectively absorbed into the magnet and flux-return structure.

Re:Not a record, but...

[atomicdragon]

Judging by the description above (yeah it can be wrong, but the site is down for the moment) this sounds a lot like the capacitor bank in the lab I work in. Unlike a tesla coil, this think puts out some serious current. The one we have will output around 120,000 amps at 5 kV. It won't be that much if say a human were in between the connections, but that would be enough to give 250 mA of current to anything with less than 20 kOhm resistance. This sounds very similar to the setup this guy has, so I imagine it can be very dangerous. The lab seems somewhat lax about some of it, but that is because a huge amount of the wiring is well enclosed, which tends to be the exact opposite of all of my home projects.

Even then you have to be careful around pulses of this much current, since often weird things happen with ground. The grounded vacuum chamber we fire this stuff into will often get potentials of several hundred volts across different parts of the same metal chamber. Or if you have something connected to ground in two ways, you can induce a current going from one ground to the other. So it is a matter of knowing what not to touch with your hands or certain equipment when the thing fires.

Re:Not a record, but...

[OOGG_THE_CAVEMAN]

OOGG WISH CORRECT STATEMENT ON IONIZING RADIATION.

ScrewMaster NOT REMEMBER PLANCK'S CONSTANT.

RADIATION TO "ionizing living tissue" MUST HAVE PHOTON ENERGY ENOUGH TO IONIZE. ATOMIC PHYSICS USE UNIT "Rydberg" IONIZING ENERGY FOR HYDROGEN ATOM.

ONE RYDBERG BE 13.6 electron volts. NOT ALL IONS REQUIRE SO MUCH, BUT CLEARLY ORDER OF VOLTS. THINK OF BATTERY; CHEMICAL BATTERIES PRODUCE VOLTS.

Planck's constant be equivalent to 3.28 10^15 Hz. Even 1 eV be 2.41 10^14 Hz, or ABOUT TEN THOUSAND TIMES HIGHER than 2.4 10^9 Hz = 2.4 GHz.

HANDY CAVEMAN RULE OF THUMB: GET CANCER FROM UV SUNLIGHT, NOT INFRARED FIRE. FIRE THERMAL BURN ONLY, NOT IONIZING.

Re:Not a record, but...

[Anonymous Coward]

You, sir, haven't got a clue as to what the hell you are talking about. Not a clue. None. Zero. You're an idiot. But there's still some hope. Enroll for a marketing degree.

"What RF? This is all Electro Magnetism"

What the hell do you think RF is, a baloney sandwich? RF *IS* electromagnetism you simple-minded fool!

"No radio waves to speak of at all from this stuff"

Really? So jumping from 0A to 100000A in a spark gap in a few microseconds won't generate any RF? Man, I wish I could slap you. With RF.

Re:Not a record, but...

[drinkypoo]

Posts like this are a big part of why I love slashdot. However you miss the point that the energy is not evenly distributed. Without a focussed signal you can get semi-random (as in, you don't know where they're going and you didn't plan for them) interference patterns. Good point about the fire, though. In order to get burned from that you're going to have to burn something 'interesting' like magnesium. and, I got a nice sunburn on my arms from arc welding while wearing a tee shirt, but that's not at all the same thing...

Re:Not a record, but...

[LoRdTAW]

"Electrocution actually isn't much of a risk with many HV devices"

You never have worked with this kind of equipment have you? ANY high voltage equipment is a risk. I once got into the hobby of playing with HV and man it is extreamly dangerous. Working with 2 60ma 12kV neons in parallel hooked to a voltage multiplier then charge a 14.4 uF 40kv pulse cap is some scary shit. 14 awg wire explodes at 35kV! I used it to crush some cans and a few quarters. I soon gave up playing with it. Small tesla coils are not lethal but the secondary sparks can burn you( larger ones are deadly). The real danger in a tesla coil are the tank caps in the tank circuit (the primary circuit). They can easily store a lethal charge. Ozone is a factor but any coiler knows of this problem. Hell the line voltage of 120 or 240 volts can easily kill you. So if any one here wants to give HV a shot I advise allot of caution and be aware that IT CAN EAILY KILL YOU!

Re:Not a record, but...

[sploxx]

> Electrocution actually isn't much of a risk with many HV devices - most will destroy themselves (or run up against current limiters) far before they output anywhere near the 200-250 mA needed to stop the human heart.

Uh oh. Be careful with such statements. I charged a PC power supply filtering cap (electrolytic, 100uF) to 600V and (accidentally) touched it with both hands. I flew across the room with a loud "ieek". I'm happy I survived that. Really. That was more than 250mA.

I have some other 10kV/1uF-Caps here, discharging them from 3kV (did not try more yet => destroyed my PC with them once because of EMI!) is enough fire, smoke and thunder to satisfy my pyromanic HV ego. I have never touched them, handle them with a 2m pole (literally!) and I'm also not going to go close to them (if charged) in any way.

Someone stated that caps charged with energies less than 10 Joule are safe (i.e. unlikely to be lethal - no warranty!), but take capacitors serious. In the setups described, the caps contains KILOjoules of energy and will SURELY kill you if you even get close to them (because of that nasty gap-jumping property of HV).

Re:Not a record, but...

[Anonymous Coward]

Gotcha OOGG, 10^14 is 10^5 or ONE HUNDRED THOUSAND TIMES higher.

Re:Not a record, but...

[Idarubicin]

Electrocution actually isn't much of a risk with many HV devices - most will destroy themselves (or run up against current limiters) far before they output anywhere near the 200-250 mA needed to stop the human heart. While a shock from a tesla coil or other HV device will hurt terribly and pose a risk of burns, it probably won't kill you.

It is true that you won't get a lethal shock directly from the high voltage side of a Tesla coil.

One thing you have to watch is the shielding on the 'low' voltage side of homemade equipment. You're going to have components running off 120 V or 240 V line current. If the high voltage side arcs to a low voltage component, suddenly you've got a conducting path through the air (technically, a plasma) attached to potentially several amps of line current. It is possible to deliver a a deadly current this way.

Aside--an arc back to the line can wreak all manner of havoc on other electrical equipment on the same circuit. Your computer won't like it, that's for sure. Please, have properly grounded metal shielding around all line conductors in your experimental area!

Re:Not a record, but...

[PurpleFloyd]

Of course it takes special knowledge to build and operate high voltage, high current devices in a safe manner; I never said otherwise. Also, if you jury-rig any wiring in order to make it work, you could very well pay with your life. High voltage and high current devices are incredibly dangerous in the hands of anyone who doesn't know exactly what they're doing. I don't dispute this. However, there are many devices in the world that are dangerous to build and operate without the proper training - aircraft come to mind immediately.

Regarding the resistance of the human body (to calculate lethal voltages), I remember being told in several HV-safety courses in physics classes that the human cross-body resistance (index finger to index finger) is generally 100 kohms to 1 mohm, depending mostly on the level of sweat on the body, and thus on environmental conditions like heat and humidity. That doesn't mean that 5 kV isn't dangerous, though: remember the 1/10/100 rule: you can feel 1 mA, can't let go at 10 mA due to involuntary local muscle contraction, and at 100 mA you are presenting a serious danger to your heart. Thus, with your 5 kV supply, you'll probably find yourself unable to let go of the power supply's terminals should you touch them. Even the voltages in your house are dangerous, in the right situation (the bathtub scenario: drop a 110v appliance into your bathtub, with you providing a path to ground, and it might not take too much to cause unconciousness and drown you). It's all a matter of knowing what you can do safely.

Re:Not a record, but...

[mshultz]

Not quite enough power for time travel, unfortunately! You've only got about half of the necessary 1.21 "jiga-watts"...

Re:Not a record, but...

[JesseL]

You've probably seen his page before because this story is a three-year-old dupe(posted by the same editor no less).

Re:Not a record, but...

[atomicdragon]

I've made the same complaint to my boss before, but he said it wouldn't make any difference since my project funds would not cover the flux capacitor, let alone a car that can handle 88 mph. He said he might consider extending the funds if I made a Mr. Fusion that worked on bananas and flat beer (I happen to work in a plasma physics/fusion lab).

But at least when we turn it up into the 8 kV range, we can brag about having a machine output a million horsepower (even if it is for 10-20 microseconds).

Re:Not a record, but...

[another_henry]

Just like to point out that although the skin effect does exist (in metallic conductors) it DOES NOT APPLY to humans. This is backed up by plenty of recent research - see the Pupman mailing list. You do not feel a shock from a Tesla coil (in theory) because the frequency is high enough that your nerves can't respond - therefore it is much less dangerous than DC or low frequency AC because there is little risk of stopping your heart. However it can and does still cause deep internal RF burns.

Actually on one of the two occasions I took a strike from my small Tesla coil, I certainly did feel it. The ground wire came disconnected and arced through me. The other time was on purpose but I carefully stood on an insulated platform and held a screwdriver to the streamers, much reducing the risk.

Re:Not a record, but...

[Anonymous Coward]

Actually, though, I have seen his page before. really cool toys, but strikes me as something most of us would probably not want to play with.

I had a electrical engineering roommate in college that used to slice beer cans in half with a powerful electric arc.

He gave it up after a particularly drunk sorority girl nearly killed herself by almost falling into the device.

As I recall... he ended up getting laid after he explained the danger of the whole situation.

Re:Not a record, but...

[mpoulton]

I remember being told in several HV-safety courses in physics classes that the human cross-body resistance (index finger to index finger) is generally 100 kohms to 1 mohm

Yes and no. When measured with low voltages, the resistance is in that range, but almost all of that resistance is in the first .5mm or so of skin. High voltages (above a hundred volts or so) instantly break down this skin barrier, and the apparent resistance drops to a couple hundred ohms. This is why 120V can kill. A 5kV capacitor bank will likely explode body parts.

Re:Not a record, but...

[Anonymous Coward]

MOD PARENT UP! Even cavemen understand ionizing versus non-ionizing radiation -- when will the rest of slashdot finally learn that cell phones and microwaves are less capable of causing cancer than VISIBLE LIGHT, for chrissake!

Re:Not a record, but...

[Anonymous Coward]

Mod that up. The point is that body-resistance is a a highly-nonlinear function of "test" voltage.

Re:Not a record, but...

[Planx_Constant]

Thank you, OOG.

Re:Not a record, but...

[Wolfrider]

--God help us if they ever had a child...

Scenario 1: Drunk-ass, brilliant but slightly suicidal HV Specialist (that can slice beer cans.)

Scenario 2: The next Tesla / Edison.

Scenario 3: Combine Scenarios 1 and 2.

Scenario 4: PROFIT!

Re:Not a record, but...

[The Wicked Priest]

I've been paralyzed by electricity. It was one of the most frightening experiences of my life.

I was just a little kid, maybe four or five. I remember this device, I think it was a humidifier, with a silver panel with a small (~1 cm) square hole, and a red panel behind the hole. I stuck my finger in the hole -- and I couldn't move. I couldn't even cry for help. Luckily my mother came by and pulled me away.

To this day, the tingling of electricity gives me the creeps. Maybe that's just normal; or maybe it has something to do with my experience. But I can't stand those touch lamps that are so popular now, because of that tingle.

Re:Not a record, but...

[WeblionX]

(because of that nasty gap-jumping property of HV).

You mean like this?

The server...

[Honig the Apothecary]

is shrinking right now before you eyes with the application of millions of /.ers.

If it gets enough hits, will it become small enough to fit in a blade system?

ya know...

[abscondment]

tesla coils are really cool. a friend and i once took a 30,000 volt capacitor bank, a homemade tesla coil and a homemade spark gap and liquified my deodorant.

his garage smelled great for a few months.

also, any time we'd point the tesla coil towards his neighbors house, they'd lose TV reception.

Re:ya know...

[Ralph Wiggam]

I can liquify deoderant with a 59 cent lighter. Good work.

-B

Re:ya know...

[Anonymous Coward]

also, any time we'd point the tesla coil towards his neighbors house, they'd lose TV reception.

Bull. Tesla coils aren't that directional. Stop making stuff up and fix your fucking shift key.

Re:ya know...

[miryth]

Stop insulting people randomly and fix your swearing problem. (meanie)

Re:ya know...

[abscondment]

the distance we're talking about is like 15 feet. we watched it happen.

Re:ya know...

[JW Troll]

my buddy built one, and it scrambled the hard drives in all his computers. also it killed radio reception in one block radius, tv too, and made the phones crap on his kitchen counter. or maybe that was the dog.

i still have the massive power transformer from it :)

Physics

[Casisiempre]

In Physics news, Slashdot effect takes another site. On to other topics...

No pictures on google's cache

[LBArrettAnderson]

If you want to see pictures of the shrunken coins..... try popular science - http://www.popsci.com/popsci/science/article/0,125 43,490445,00.html

Re:No pictures on google's cache

[LBArrettAnderson]

or here's a link without the space

Re:No pictures on google's cache

[sumdumass]

http://images.google.es/images?&q=+site%3A205.243. 100.155+jpg&btnG=B%C3%BAsqueda+en+Google

i think that is a image cache of it
to bad i don't know how to make a nice little link for it.

Not a Mirror, But Related

[Anonymous Coward]

http://www.thegeekgroup.org/

These guys do a lot of the same stuff.

Re:Not a Mirror, But Related

[another_henry]

Or rather did, before they stopped doing interesting things a year or so back and started threatening to sue a guy for "stealing" an image from their website... which they turn out to have got from someone else anyway, the same guy the accused got it from!

They are also big on posting unsubstantiated claims to the list and this has really harmed their credibility.

So.... why does this happen?

[mark-t]

Since the site is slashdotted to the ninth circle of hell and beyond, and the google cache links don't refer to any of the theory pages, would someone be willing to explain exactly how this works and why it happens?

Re:So.... why does this happen?

[multipartmixed]

Electrons moving in a wire exert a magnetic force.

A lot of electrons moving in a wire exert a lot of magnetic force.

If you use coiled wires, you get a cylindrical magnetic field.

If you put a coin inside a coiled wire with a lot of electrons moving through it, it gets smooshed.

Re:So.... why does this happen?

[yo303]

From PopSci:

Bert's high-voltage equipment takes up most of his screened-in porch (from the looks of things, his wife drew a line at the sliding door?there's a clear border between tidy suburban house and chaotic suburban lab). Bert begins the coin-shrinking process by wrapping a quarter in copper wire and bolting the leads to copper bus bars, which are connected, by way of a triggered spark gap, to a 600-pound bank of 12,000-volt capacitors. A bulletproof blast shield encloses the coin and coil, and a high-voltage power supply charges up the capacitors. The only thing holding back the several thousand joules of energy stored in the capacitors is the tiny space between the spark gap's two brass discs.

Pressing a switch triggers the spark gap, which releases the entire charge through the coil in 25 millionths of a second. This creates a huge magnetic field, which induces a current and then a magnetic field inside the coin, which in turn pushes back against the field outside. The repulsion force between these two fields crushes the metal, instantly taking a quarter down to the size of a dime. A large amount of energy discharged in a short amount of time usually entails an explosion, and in this case the copper coil is blown apart with a brilliant flash and a satisfying bang. And, yes, the report is sharper than any drum, proving that you really can hit something as hard with magnetic force as you can with a drumstick.

yo.

Re:So.... why does this happen?

[Jardine]

I wonder what would happen if this was done to a Canadian 2 dollar coin (also known as a twonee). Instead of being made with a single metal (or a bunch of metals mixed together), this coin has two seperate sections. The middle is mostly copper and the outside ring is nickel

Re:So.... why does this happen?

[0x20]

American coins are sort of like this too - made of layers of differing metals or alloys. Quarters, nickels and dimes are pure copper inside, clad with a mixture of copper and nickel. Pennies are zinc plated with copper.

I think that there is enough space between the particles in the metals at the newtonian scale that there should be no significant size difference between two different metals being shrunk by this method. At the atomic or subatomic scale, there might be a measurable difference difference, but i doubt it would be enough to affect the bond between the outer ring and the center. But who knows? It would be an interesting experiment.

Re:So.... why does this happen?

[no longer myself]

I'll decent from the first reply... (no offense 0x20)

This is just a guess, but fromt he pop-sci article (link somewhere above) the image of the shrunken penny (US) was dramatic while the image of a nickle (US) was much less so. I'd hypothesis that the copper portion would shrink at a much higher rate and fall out of the center.

Then again, US coins aren't made of pure elements these days, so who can tell...

Re:So.... why does this happen?

[Anonymous Coward]

Quarters, nickels and dimes are pure copper inside, clad with a mixture of copper and nickel. Pennies are zinc plated with copper.

What he's referring to looks rather different: twoonie image (1 picture == 1kw). Basically, it's like there's an annular coin and a central coin inside it. Dunno if there's any way to separate them, short of dissolving one.

The first coin of this type that I saw was the late lamented 500-lira piece. Apparently the 1-euro and 2-euro coins are also like this, but I haven't handled either of them yet.

I think it looks kind of neat, but I don't mind the US not having one. We are very conservative with our currency design, and I like it that way.

I think that there is enough space between the particles in the metals at the newtonian scale that there should be no significant size difference between two different metals being shrunk by this method. At the atomic or subatomic scale, there might be a measurable difference difference, but i doubt it would be enough to affect the bond between the outer ring and the center.

You misunderstand what this process does. It squeezes the coin radially inward. It does not affect the density of the metal. (It is still an amazing thing of course.)

Re:So.... why does this happen?

[0x20]

I guess I don't understand how a material can be squeezed inward without affecting its density. same mass in smaller volume = greater density, right?

Re:So.... why does this happen?

[Spacejock]

In a nutshell? He's deflating US currency.

Re:So.... why does this happen?

[zeno_2]

The coin gets a bit thicker.

Re:So.... why does this happen?

[1u3hr]

I guess I don't understand how a material can be squeezed inward without affecting its density. same mass in smaller volume = greater density, right?

same mass in smaller area = greater thickness

Get some play-doh. Make a cylinder. Squeeze it. Now the diameter is smaller, but it's longer. Conversely, make a disk. Slap it. Now it's got a larger area but is thinner.

In all cases volume and density are unchanged. Unless you push it through a phase transition to a stable denser state, like carbon to diamond, when the pressure is removed it will rebound to the same volume, if not shape.

Re:So.... why does this happen?

[juhaz]

Apparently the 1-euro and 2-euro coins are also like this, but I haven't handled either of them yet.

They are.

Pre-Euro Finnish 10mk coin was like this as well.

Re:So.... why does this happen?

[Planx_Constant]

I don't remember if it was this site or not, but I remember seeing a coin like you describe that had been magnetically shrunken. The inner coin contracted more than the annulus and fell out.

working link

[Nf1nk]

for the love of god put in a working link

Re:working link

[Mark J Tilford]

slashdot puts in occasional spaces to prevent people from adding overwide lines to pages.

Tesla Coils and other cool stuff

[Temporal Outcast]

See Sam Barros' Powerlabs for similar stuff - the guy has got a lot of very cool and realy interesting stuff.

Especially interesting are his high-voltage stuff.

Is this legit?

[adept256]

Can't you get in trouble for monkeying with currency?

Very cool, though.

Re:Is this legit?

[hyu]

Never mind that. What's more important is figuring out how to keep track of your change when it gets that small. It's hard enough as it is.

Re:Is this legit?

[Anonymous Coward]

No.

Re:Is this legit?

[Anonymous Coward]

Not sure, though I know for a fact that you can get in trouble for applying current to a monkey.

Re:Is this legit?

[The-Dalai-LLama]

From parent:

Can't you get in trouble for monkeying with currency?

This was discussed in an earlier thread about some guys that nuked a stack of $20's looking for RFID tags (though I'm having trouble finding the article) and IIRC, the topic is dicussed here, as well.

The Dalai Llama

"I write messages on money. Its my own form of social protest. A letter printed on paper that no one will destroy passed indiscriminately across race, class And gender lines And written in a blood that keeps the beast alive. A Quiet little hijacking on the way to the check-out counter And a Federal crime. I hope that someone will find my message one day when they really need it. You Are Not A Slave" - some guy on the liner notes for a Rage Against the Machine Album

Re:Is this legit?

[Peale]

U.S. Title 18, Chapter 17, Section 331: Prohibits among other things, fraudulent alteration and mutilation of coins. This statue does not, however, prohibit the mutilation of coins if done without fraudulent intent if the mutilated coins are not used fraudulently.

See http://www.pennysmasher.com/

Re:Is this legit?

[ProKras]

This stuff is covered in the US Code Title 18, Chapter 17 .

Companies selling souvenir penny-pressing machines often cite Section 331, which says currency may not be defaced for fraudulant purposes. However, section 333 says that it is unlawful to alter the money "with intent to render such bank bill, draft, note, or other evidence of debt unfit to be reissued." I suppose the shrunken coins would be "unfit to be reissued," but then again so would souvenir squished pennies.

Re:Is this legit?

[Ironsides]

Link on the RFID Cash Original: http://www.prisonplanet.com/022904rfidtagsexplode. html Sequel: http://www.prisonplanet.com/180304_RFID_article.ht ml

Re:Is this legit?

[jaoswald]

Section 333 refers to "National bank obligations", roughly, paper money.

The idea behind the "fit to reissue" concept is that paper money (when the U.S. was on the gold standard) represented gold in some bank vault, and the bank printed only as many bills as it had gold. If you brought the bill back to the issuing bank, you could get the gold, if you wanted, or the bank could destroy the old bill and print a fresh one. Always preserving the link between paper money and the gold backing it.

If you alter the bill so that the bank can't tell anymore that it is valid, or can't tell how much the bill is worth, then you've broken the link. The risk is that the bank might be fooled into printing more paper money than it has gold to back it (OH MY GOD! THE GOLD STANDARD HAS COLLAPSED! RUN FOR YOUR LIVES!), or they will fail to replace a bill, meaning that there will not be as much paper money as gold. That is not a crime against the gold standard, but still causes a problem: if you run out of paper money, you have to use coins or barter, which are inconvenient, or wait for more gold to be dug out of the ground and end up in a bank vault somewhere.

Of course, none of this gold standard nonsense applies anymore, but it is still good to have laws to protect paper money.

Re:Is this legit?

[sploxx]

C'mon, mods, this is NOT A TROLL. This is a serious question IMHO!

Re:Is this legit?

[sisco]

The coins would certainly be "unfit for reissue" but the line "with *intent* to render...." is a little bit vague.

I'm sure these guys were making every effort to shrink the money without rendering them 'unfit for reissue.' So that makes it legit right?

(laugh its funny)

How is this any different from say

[OverlordQ]

PowerLabs?.

Does the metal become more dense?

[gopher_hunt]

I don't understand where the metal goes. Do the coins weight the same before and after?
I was under the impression that most solids wouldn't compress this much.

Re:Does the metal become more dense?

[Anonymous Coward]

The coins do in fact weigh the same after the shrinking. They actually get a little fatter in the middle but with a smaller diameter. Take a look at one of his e-bay auctions and he has a little explanation on there and a pic!

Re:Does the metal become more dense?

[JackpotMonkey]

This would be somewhat similar to the pressures exerted onto a lump of coal to create diamons, every piece of matter has alot of airspace between its atoms, the great force created here is simply squeezing some of it out creating a denser object.

Re:Does the metal become more dense?

[eclectro]

What happens is the coin ends up _thicker_ than before. Because it is thicker, the coin in turn becomes smaller. The mass is indeed the same before and after.

There is no exotic atomic manipulation going on. Not that people have tried (aka alchemy).

Here are his ebay auctions

Re:Does the metal become more dense?

[miryth]

Hmm, alchemy... "Hey look, I turned this quarter into gold!" "Really? How much gold?" "Er, about 25 cents worth..."

Re:Does the metal become more dense?

[Anonymous Coward]

They don't compress at all, they deform. The coins are thicker than they were, more of a metal slug shape. Unfortunately it's not clear in any of the popsci or ebay pictures (no side views), but it is described in the page text (mirrored in a comment here).

Obviously "shrunk" is a bit of a misnomer, and really they're squeezed. Much the same as what happens on the railroad tracks, but on a different axis. :)

Re:Does the metal become more dense?

[Anonymous Coward]

Yup, that would be neat if:

a) it were possible with a metal
b) the page text didn't state "A shrunken coin weighs exactly the same as before, and its density is also unchanged. The coin does get thicker as its diameter is reduced."

Re:Does the metal become more dense?

[1u3hr]

This would be somewhat similar to the pressures exerted onto a lump of coal to create diamons, every piece of matter has alot of airspace between its atoms, the great force created here is simply squeezing some of it out creating a denser object.

All of the above is completely wrong.

Re:Does the metal become more dense?

[Raffaello]

every piece of matter has alot of airspace between its atoms

That would be vacuum space, not "airspace." There is no air between the atoms of a metal solid.

Other links to shrunken coins (still up)

[ClockChaos]

http://www.popsci.com/popsci/science/article/0,1 25 43,490445,00.html

http://home.earthlink.net/~smalldollars/dollar/a dd 005.html

Re:New experiment...

[francium de neobie]

You can do that with magnifying lens

Shrinking the national debt...

[SmackCrackandPot]

With some slight modifications, this technique could be used to shrink the national debt.

Re:Shrinking the national debt...

[eclectro]

With some slight modifications, this technique could be used to shrink the national debt.

Only if you electrocute the politicians currently in office.

Re:Shrinking the national debt...

[jcuervo]

With some slight modifications, this technique could be used to shrink the national debt.

Yeah, but you'd have to run 10,000 volts through George --

Only if you electrocute the politicians currently in office.

-- damn, beat me to it. :P

Maybe, Just maybe...

[Anonymous Coward]

he could apply this to the record holding 0.85 HD. Then the same drive could hold the smallest and second smallest records!!

How shrinking a quarter works

[Anonymous Coward]

* Theory of Operation
* Results
* EM Field Theory and Wire Fragmentation?
* Isn't Defacing Money a Federal Crime?
* So Who Invented this Crazy Device?
* References

Theory of Operation:
The Quarter Shrinker uses a technique called high velocity electromagnetic metal forming, or "Magneforming". This technique was originally developed by the aerospace industry in conjunction with NASA, and has been popularized by Aerovox, Grumman, and Maxwell. It involves quickly discharging a high energy capacitor bank through a work coil to generate a very powerful and rapidly changing magnetic field which then "forms" the metal to be fabricated. While it works best with metals of relatively high electrical conductivity such as copper or aluminum alloys, it will work to a more limited extent with poorer conductors such as sheet steel.

In my current system, I charge up a large capacitor bank consisting of a number of large capacitors, each weighing about 165 pounds and about 30" high x 14" wide x 8" thick. A High Voltage relay is used to connect the caps either to a high voltage DC charging supply, or to a high power bleeder resistor chain. A 15 kV 60 mA transformer and a set of 40 kV rectifiers provide the DC charging voltage for the capacitor bank. The primary of the transformer can be overdriven to 140 volts via a variable autotransformer to speed up the charging process. The electrical energy stored in the capacitor bank is proportional to the square of the bank voltage, and the degree of "shrinking" force is directly proportional to the capacitor bank's energy.

The charged capacitor bank is quickly discharged through a single layer work coil made of heavy magnet wire. The coin is held firmly in the center of the coil by a pair of dowel rods so that it's axis of rotation is parallel to the centerline of the coil. This constrains the coin from twisting, and also helps balance the forces wanting to eject it from inside the coil. The two ends of the coil are stripped of insulation and firmly bolted to heavy copper bus bars. The high voltage "switch" that connects the capacitor bank to the work coil is actually a high power triggerable spark gap, called a "trigatron". The main gap electrodes are solid brass, 2.5" in diameter. One of the electrodes is drilled and tapped to hold the triggering electrode (actually a modified spark plug). A triggered spark gap is the only affordable device that can hold off the high voltage and then reliably and efficiently switch the high currents involved in the shrinking process (70,000 to over 100,000 amperes).

The trigatron is fired by applying a high voltage (~40 kV) pulse to the trigger electrode, which then causes the main gap in the trigatron to ionize and fire. Once the main gap fires, current rapidly climbs in the work coil, the rate of change (di/dt) being of the order of 4-5 billion amperes/second. The natural resonant frequency of the LC circuit formed by the capacitor bank and work coil is of the order of 8-12 kHz. Through transformer action, a huge circulating current is induced in the coin, but because of skin effect, this current is confined to the outermost rim of the coin, typically penetrating to a depth of less than 0.050". In clad coins more of this circulating current flows through the better conducting copper center of the clad sandwich than in the outer layers. The coin and work coil magnetic fields oppose each other (Lenz's Law), resulting in tremendous repulsion forces between the work coil and the rim of the coin. The circulating current in the rim of the coin actually prevents the rapidly increasing magnetic field of the work coil from penetrating the interior of the coin.

The large current that's induced into the outer rim of the coin can reach a million amperes or more! The initial bank energy is typically in the range of 3,500 - 8,500 Joules (or watt-seconds) but it is being discharged in microseconds. As a result, the instantaneous power is quite large, and for a brief instant is roughly

As seen on Ebay

[Jim Buzbee]

Check out the picture and prices of the some of his work on ebay

Try slashdoting that!

anti-spam

[mnewton32]

Please Contact Me me to discuss YOUR custom shrinking needs!

Ah, now this is a welcome relief from all those spammers who seem to think I always need to make things bigger!

Dammit

[ScrewMaster]

"Too many users attempting to access this site."

I wanted to see his Tesla coil info. Damn.

Re:New experiment...

[Jorkapp]

Obligatory Simpsons Quote

[Body Guard #1] Hey boss, we were just thinkin' of you.
[Quimby] You idiots! You're fired!
[Body Guard #1] Oh yeah. Then who will take a bullet for you?
[Body Guard #2] Or hook your genitals up to a car battery?
[Quimby] I'll tell you who. This man! (points to Homer)
[Homer] Woohoo!
[Marge] Homer, didn't you hear...
[Homer] (Interrupting) I said Woohoo.

-1 Fucking Redundant

[Anonymous Coward]

Who cares if it has been said yet in response to this story, any joke about servers or bandwidth has been made at least 10,000 times before.

Please stop these jokes - really, I'm begging you.

Site slash doted

[NIK282000]

It might be my finiky pc but i think we just /.ed another site. Great topic though.

Google Image Cache

[YearOfTheDragon]

Google Image Cachebr

Magneforming

[Animats]

Magneforming is a routine industrial operation. Because it produces a true radially symmetrical squeezing force, it's often used for operations that involve compressing a tube around something. I first saw it used in making hydraulic valve bobbins. These have a machined metal core with "piston rings" compressed around key areas.

Magneforming is just another less-common metalworking techniques. Others include hydroforming, water jet cutting, spinning, and blowing.

Okaaaaayyy...

[Xenographic]

Err, how exactly does one do that with a Tesla coil?

Shock the employees at your ISP until they upgrade your services?

Or have you been playing too much Starcraft? :]

My god

[rune2]

We've even Slashdotted the pics on the cached sites! Looks like the quarters aren't the only thing being crushed. I'm sure the webservers have imploded by now...

funny little story

[Paul d'Aoust]

ha ha, funny little story about our twoonies. When they began to make them, there was something wrong in the design -- maybe the join between the annulus and the inner coin wasn't as tight as they'd intended, or maybe the composition of metals wasn't quite right, but when they got too cold the inside would contract faster than the outside, and the coins would fall apart.

Living near Las Vegas?

[ebrandsberg]

If he lives near las vegas, it might explain the mysterious EMP that in theory caused a bunch of car keys and other alarms to stop working. In any case, I hope his neighbors arn't trying to use WiFi to connect two computers, cause his work will probably knock anything off. Forget about FCC certification on his equipment...

Wayback Machine

[wideBlueSkies]

Better than a mirror: The Wayback Machine!

Try looking here.

Or here.

The archives are kind of old (pre 2004) but they seem to have some of the information.

The "news for nerds treatment"

[Nick Driver]

I'm happy to see the site finally get the news for nerds treatment it deserves

Yeah! That's even got a catchy ring to it... From now on, when we want to bring a site to its knees, we'll give it the news for nerds treatment. :-)

Re:The "news for nerds treatment"

[Anonymous Coward]

us nerds never get much of anything on its knees...

Re:The "news for nerds treatment"

[Anonymous Coward]

Now all you need to do is figure out a way to run apache on a woman, and post her URL to slasdot. Just be sure to be close by when the slashdotting brings her to her knees...

Since people are interested...

[Ironsides]

Here is a link to a site on Tesla Coils, since so many of you seem to be interested in them.

http://www.eskimo.com/~billb/

Has no photos :-(

[Nick Driver]

Unfortunately the Wayback Machine doens't have any of the pictures archived.... only has the text :-/

Re:Has no photos :-(

[wideBlueSkies]

It has some of them. Sometimes you have to click on the thumbnal placeholders to get at the pictures. Click around.

I admit that it's not perfect, but it's still better than the /.-ed site.

wbs.

Patent?

[Salamander]

Looks like the US Air Force's Rome Air Development Center thinks they have a patent on it. Am I the only one who thinks "United States of America as represented by the Secretary of the Air Force" should not be a valid patent assignee?

Re:Patent?

[Jimithing DMB]

Am I the only one who thinks "United States of America as represented by the Secretary of the Air Force" should not be a valid patent assignee?

huh? The U.S. government is a quite good patent assignee. Think of technology developed by or for NASA. In fact, I work on an image enhancment technology which was originally done by my company for a NASA contract. If you read the patent application, it has our employee's names on it along with the U.S. government.

After developing this we turned around and purchased a license so we could use the algorithm in our own software projects (i.e. PhotoFlair). That means that the government is able to use the technology and so are we. The government doesn't have to pay us anything to use our algorithms.

I don't think there's anything at all wrong with that. The algorithm was developed on their dollar and so they have the rights to implement the algorithm however they wish.

In fact, it seems to me that (for a change) the patent system is doing exactly what it is supposed to be doing!

Re:Patent?

[Salamander]

If it was developed at public expense, it should be placed into the public domain, not patented and subject to royalties.

Re:Patent?

[eMilkshake]

I could see that the largest reason for the government to patent something would be so they didn't have to pay another party royalties for what they, themselves developed. Imagine if NASA developed something, couldn't patent it, then I patented it, and demanded payment.

Just because there is a patent doesn't mean that royalties will be demanded, but I don't know the practice.

Re:Patent?

[Salamander]

Imagine if NASA developed something, couldn't patent it, then I patented it, and demanded payment.

If NASA disclosed the invention without a patent, that would be prior art and would prevent anyone else from patenting the same idea.

Just because there is a patent doesn't mean that royalties will be demanded

The RADC page above specifically mentions that they expect to make money from royalties.

Re:Patent?

[Raffaello]

If it were put into the public domain, then third parties from other countries could use the technology without paying any licensing fees. If the US government holds the patent, they can, at their discretion, license it free of cost to US governments agencies, and US nationals, but charge others a licensing fee. Moreover, if it is a strategically sensitive technology, the US government can deny licenses to companies or nationals of certain unfriendly countries. This would not be possible if said patent were put into the public domain. Would denying a license stop illicit use? No, but it would make doing business in the open impossible.

This way, taxpayers benefit from patents created on our dime, but we don't give away the fruits of our tax dollars to those who did not pay for them (i.e., everyone who is not a US taxpayer), and those who are actively hostile towards the US.

Wrong Fun

[Jman314]

Submitter got it wrong: Physics is F=uN!

(You know, force equals mu times N, friction and stuff? Never mind.)

Re:New experiment...

[foo1752]

Wonder if he can do the opposite with my...uhum...private parts?

Interesting idea... So, the article claims that it takes 100 kiloamps of current to shrink a coin. So, let's just assume that the process is reversible and by finding a way to enlarge a small coin, you would actually be generating large amounts of current, okay?

Now, let's throw your genitals into the mix. We'll take your small, unused organ and hook it up to the power grid. Then, we'll order some penis enlargement pills and feed them to you in mass quantities. Step 3: profit from selling the energy back to the power company!

You missed one

[Seraphim_72]

the extremely slight risk of cancer

YMMV but I prefer to keep cancer at bay, my Father just got the news of prostate cancer. Let me guess PurpleFloyd you are in your 20's (as am I) and you are going to live forever.

Sera

Re:You missed one

[Thomas Shaddack]

There are worse cancerogens than electromagnetic fields. Fried foods, air pollution, stress...

Something like this:

[itomato]

A twonee would probably react like this 10 Franc coin: Tiny cached thumbnail en Espanpol

No website

[thellamaman]

No web site is configured at this address.

Sounds like, "These aren't the coins you're looking for."

Re:No website

[ErichTheWebGuy]

Sounds like his host pulled the site cuz it got ./'d
They use IIS so they shoulda come up with that irritating microsoft error page, something like:

These coins cannot be displayed
--------
The coins you are looking for are currently unavailable. The coins may be experiencing technical difficulties, or you may need to adjust your shrinking settings.
---------
Please try the following:

- Click the "Shrink Again" button, or try shrinking again later
- If you typed the name of the coin in the address bar, be sure it is spelled correctly
- To check your shrink settings, click the Tools menu, then click Currency Settings. On the Size tab, click settings. Those settings should match those given to you by your coin administrator.
- If your coin administrator has enabled it, Windows can detect the size of your coins automatically. Click -detect coins-
- Some coins require 100K Amp shrink power. Click the Help menu, and click About Microsoft Coin Shrinker to determine if you have 100K Amp shrink power installed.
- If you are trying to reach an already-shrunk coin, make sure your shrink settings can support it. Click the Tools menu, then click Shrink Options. On the advanced tab, make sure the MS-Voltage 3.1, MS-Amperage 2.2, and MS-Wattage 2.5-SP1 are checked.
- Click the -back- button to try another coin.

Cannot find coins or shrink error
Coin Explorer

Conservation of matter and energy?

[Magic5Ball]

So wait... If it squeezes a quarter down to the size of a dime, does the density of the coin increase to fit the same number of atoms in a smaller space, or is some of the matter from the original coin lost/converted in the process?

Re:Conservation of matter and energy?

[Anonymous Coward]

Neither. The coin has the same weight and just gets thicker.

Re:I thought this was illegal?

[sisco]

refer to posts further up the page. we had a nice little discussion about it, and somebody found the actual quotes of some of the laws.

are we sick or what? :-)

interesting, but is it actually reversible?

[Anonymous Coward]

so can any of the physics nuts out there tell me if this process is reversible? Is it possible to use the same/similar technique to make coins "expand" ?
I am assuming there must be a way.

I think making coins larger would be a whole lot more interesting, and I'll assume by the details of this process that making a coin twice as large makes it half as thick... I'm talking coins here people! lol

the mass and weight would remain constant, has to, but I'd think large sized coins would be more of a novelty than small ones...

one method for doing this (works) is to put your coins on the railway track just before a train comes along... makes your coins all nice and squished out... kids - dont try this at home...

Re:interesting, but is it actually reversible?

[Mongo222]

Yes, the device used to expand the coins is fairly common... It's called a "Deasel Locomotive". PLace the coin on a nearby set of train tracks, wait for the Locomotive device to be applied to the coins surface. After treatment the coin will be significanlty expanded.

WORST TROLL EVER

[Anonymous Coward]

You mean like this?
Hello, I'm WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW WIDE! Yes, I'm WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW WIDE! Very very WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW WIDE! So wonderfully, so fantabulously WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW WIDE!


Your comment violated the "postercomment" compression filter. Try less whitespace and/or less repetition. Comment aborted.Reason: Don't use so many caps. It's like YELLING.Reason: Don't use so many caps. It's like YELLING.Reason: Don't use so many caps. It's like YELLING.Your comment violated the "postercomment" compression filter. Try less whitespace and/or less repetition. Comment aborted.Your commeYour comment violated the "postercomment" compression filter. Try less whitespace and/or less repetition. Comment aborted.nt has too few characters per line (currently 33.9).Your comment has too few characters per line (currently 33.9).Your comment has too few characters per line (currently 33.9).Your comment has too few characters per line (currently 37.3).Your comment has too few characters per line (currently 37.3).Your comment has too fewYour comment violated the "postercomment" compression filter. Try less whitespace and/or less repetition. Comment aborted. characters per line (currently 37.3).Your comment has too few characters per line (currently 37.3).Your commeYour comment violated the "postercomment" compression filter. Try less whitespace and/or less repetition. Comment aborted.nt has too few characters per line (currently 37.3).Your comment has too few characters per line (currently 37.3).Your comment has too few characters per line (currently 37.3).Your comment has too few characters per line (currently 37.3).
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Re:working link
Re:working link (Score:1)
by Mark J Tilford (186) on 09:46 PM March 19th, 2004 (#8617899)
slashdot puts in occasional spaces to prevent people from adding overwide lines to pages.
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Re: Political Tangents

[zedmelon]

To continue in this direction, I recently watched (History Channel, I'm pretty sure) a blurb that stated Carter (forever marked by millions for the Olympics, hostages, etc) actually did nearly all the negotiating--personally, I seem to recall--to get the hostages released, but since it didn't actually happen until Reagan took office, Reagan got the credit.

"...but things don't become noticable until Guy B is in office, and gets blamed..."

I don't know how true that is, but I'm willing to bet it's a lot more than most of us realize.

[further]I was pleased when Reagan was elected because I didn't like Carter, based solely on the anger I felt when he beat Ford in the '76 election. Ignorant? Yes, but I was five, so neener neener.[/tangent]

Why not simply softwrap text over 120 characters?

[DrMorpheus]

Come on, this is HTML 101 stuff.

Internet Archive

[san diego codepig]

You can see the web pages at http://www.archive.org/. Just cut and paste any URL into the 'Wayback Machine' and you can see archived versions of the page.

I noticed on some pages (the Quarter Shrinking Theory page) the text is 'invisible' using Firebird, but you can read it by selecting the entire page (ex. ctrl-a) which highlights everything.

I've done this in the past with slashdotted sites and it seems to work most of the time.

High Voltage Diamond Making Machine...?

[cr0sh]

Here's an idea:

1. Form a dense carbon sphere. Form a dual halve alluminum sphere whose halves smoothly mate together. The sphere is actually a shell, with very thick walls, which surrounds the carbon sphere. For instance, a 3cm outer shell, 1cm thick wall, leaving a 1cm diameter inner sphere for the carbon. Pins hold the sides together.

2. Suspend this sphere in the middle of a very large version of the work coil as described on the site. The machine is also large - maybe building size capacitors, etc.

3. Charge the puppy up and fire it...

Could you end up with a diamond? Who knows...

Re:High Voltage Diamond Making Machine...?

[deimtee]

No you wouldn't get a diamond.
The force is directed radially inwards along a cylinder.

To make diamonds you would need a spherically uniform force.(And probably a lot more megapascals.)

However you would probably get a really neat pancil!

-deimtee

Re:High Voltage Diamond Making Machine...?

[cr0sh]

I kinda realized that when I posted it (that the force would be radial, instead of spherical) - which is why I suggested the spherical alluminium shell, though that would end up with a hourglass shape in the end.

I would think it would be possible to make a nearly spherical field - maybe using three coils orthogonally opposed? Or maybe using more than three coils?

As far as the energy required, I also realized that it would be a huge amount, perhaps more than the resulting diamond (if it worked, that is), would be worth. Heck, the cost of the capacitors and building(s) to house them would likely be a major limiting factor. Also note that I was thinking of this size (very huge) in regards to the starting size of the carbon sphere (1cm) - leading to a much smaller potential chunk of "diamond", if it worked...

Re:Google Cache no -- use the Wayback Machine

[1u3hr]

archive of teslamania.com, which DOES have images.

My Two Cents

[wildsurf]

Finally, someone who can correct the historical accident that nickels are larger than dimes!!

Now, if only he could find a way to GROW money... or would that merely consist of nickel-and-diming people to death?

Re:My Two Cents

[Anonymous Coward]

Used to be that a nickel was 5 cents worth of nickel. A dime was 10 cents worth of silver. Thats also why dimes and quarters had groves, so you couldn't shave a bit of silver off of each coin you had. Nickels and pennies weren't worth it. Most coins are alloys now though.

Re:My Two Cents

[the pickle]

Finally, someone who can correct the historical accident that nickels are larger than dimes!!

That isn't historical accident. It was intentional. Silver got pretty expensive in the late 1860s, and by 1873, the "half-dime," which had been an integral part of US coinage since 1794, would have had to shrink yet again to prevent its intrinsic value from growing greater than its face value.

The nickel five-cent piece, introduced in 1866, was the solution to this problem: a coin that didn't fall through tiny holes in one's pocket, had some substantial weight to it, and was far easier to deal with in general. It took another 91 years for the price of silver to get high enough to make dimes, quarters, and half-dollars impractically expensive. (This was at least in part due to the fact that many world governments were still on the silver standard as late as the mid-1960s, which kept silver prices artificially low.)

Ever seen a half-dime? They're pretty literally a half of a dime, maybe 2/3 as thick and 2/3 the diameter (don't have exact dimensions in front of me) of a modern US 10-cent piece.

BTW, it isn't historical accident that a US one-cent piece is larger than a dime, either, although the solution to rising copper prices in the 1970s was (starting in 1982) simply to copper-plate zinc cent planchets instead of making them from solid copper.

p

Diamond?

[wildsurf]

Using this technique, could you put in a lump of coal and make a diamond?

If not, how about a lump of coal surrounded by metal to squeeze it? Very spark-ly...

Dupe -or- Search? Slashdot? Yeah, right....

[siglercm]

Five minutes of looking proves to me that Slashdot's search engine is basically worthless. My memory's not *that* good....

This post is a dupe. I remember seeing an interesting slashdot story, God knows when, and I looked over both the Powerlabs and Teslamania websites. I vividly remember the (now slashdotted to hell) shrunken coins. But, then again, if you're only 18 minutes old, you wouldn't know that, now would you?

The more I read Slashdot, the more I feel like some new-age Methuselah in a sci-fi story, where all those around me are younger, and their 80 year lifespans appear like those of a fly.

Clemmitt

Re:I thought this was illegal?

[sjames]

Once and for all, it's only illegal if done fraudulantly. In other words, you can alter the coin in any way you like as long as you don't try to pass it off as anything else.

So, re-forming a half dollar into a dollar coin is a crime. Re-forming it into a shrunken coin or a ring, stamping someone else's face on it, etc and selling it as a novelty is not.

Ummm shrunken coins isnt legal

[nurb432]

You cant legally deface US currency..

While cool, its like sending a note to the feds, "come arrest me, here is where i live"...

Mod Parent Up

[Anonymous Coward]

If lawyers tried to be engineers, they'd sound similarly-stupid, and you've illustrated that point perfectly.
me

Shrink..No...Hotter than Hell with 1 Battery, YES

[SuperGlue]

I am not sure about shrinking coins, but, it was very easy for me to make about 10 coins Hotter than Hell!!!
(Thanks to my 2 yr old son)

Every morning when I leave for work, I grab a handful of change for soda money.

I am at work for around 5 hours when, I suddenly felt like my pocket was going to burn through my pants. I reached in my front pocket and quickly threw out everything I could grab. The burning contents of my pocket landed on the desk and all my coworkers started to look at me like I was some sort of insane madmad (but of course).
I looked at the stack of coins that fell on my desk and also I noticed ...... 1 rechargeable AA battery.

I had never seen the battery earlierwhen I was grabbing the coins and I was quite oblivious to the impending Solar Flare that was about to go off in my pocket.

I guess during the day, those coins shuffled themselves around until they finally completed the circuit. Once they did ..... Owwwww!!!!

A coworker of mine reached out to grab one of the nickels on the top of the pile of coins. It had been 3 or 4 minutes later and quickly found out that they were hot enough for him to yell out in pain too..... :)

SuperGlue

Re:How shrinking a quarter works

[Anonymous Coward]

The apparently "unpredicted" tensile failures are probably caused by pinch instabilities in the current a la the instabilities that render everything from a zeta-pinch to a tokomak unworkable. Yes, this is copper wire and not plasma, but the currents are high enough to cause the copper to flow plastically, and hence the appropriate analysis requires the use of equations that show this instability in their solutions.

Re:Dupe -or- Search? Slashdot? Yeah, right....

[siglercm]

I'm not sure whether to be pleased that I got a mod point, or disappointed that I was modded as "funny."

Sad, isn't it?

Clemmitt

Re:Ummm shrunken coins isnt legal

[windex82]

Yeah thats why they have those coin smashng machines at amusment parks... im not claiming it isnt technicly illegal but the treasury has better things to do then worry about pennies..

Re:Shrink..No...Hotter than Hell with 1 Battery, Y

[Anonymous Coward]

I remember a similar news story a few years back...

Some cop was keeping loose ammunition in his pocket with a portable rechargable walkie-talkie. The brass casing of the shells came into contact with the recharging terminals of the radio and got hot enough to explode a bullet.

See slashdot effect in action

[Via_Patrino]

See slashdot effect in action here and here

You're wrong

[Anonymous Coward]

a poster upthread mentioned that it's illegal to deface or mutilate currency FOR FRAUDALENT PURPOSES. It's a matter of intent. Thus, it is clearly legal in this instance. To prove it illegal, you must first prove intent to defraud.

MOD PARENT TROLL

[ultranova]

The parent is troll, not insightfull. Unless untrue (popular pictures take a few minutes max to be found) disparaging remarks are now considered insightfull ?

And even if the parent were true, it would better to wait a weekend for the pictures to appear, than to destroy a website, perhaps permanently (if the provider will kick the website out or give the owner a huge bill for bandwith overuse).

Who modded parent insightfull anyway ? Are the trolls forming some kind of clubs, modding each other up ?

Re:Ummm shrunken coins isnt legal

[The Wicked Priest]

But they aren't defaced. I see the faces plainly. They're hardly even distorted.

It is not the coin that shrinks . . .

[wornst]

but your mind.

The Slashdot Effect

[GDaddy]

So, I'm undecided, is it morally wrong to submit a small website for a slashdot story, knowing full well that that site is going to get shutdown inside of 24 hours?

It seems to me a more responsible article would be about the concept of coin shrinking in general, and perhaps only link to the google search results.

As it stands, this article did nothing but direct the slashdot readers' attention to the concept, and then demonstrate that some poor guy's page is unavailable, before going on to show us a googled list of sites.

Re:Ummm shrunken coins isnt legal

[Beolach]

Yes, it is illegal. The penalty is that the currency becomes void. So you can't pay for anything with any of your shrunken (or stretched) coins.

Re:Deflation?

[SAPHRguru]

But now it's concentrated... doesn't that make it more valuable?