The earlier Jacob's Ladder I made was a wooden folding toy; this is the more famous electric one. They have nothing to do with each other.
My Jacob's Ladder does what people told me couldn't be done: I obtained over two feet of travel, with a nice spark using a neon sign power supply that "only" puts out 5000 volts (5kv). Also, no Gabriel Circuit on it. I did add a tiny twist of copper wire at the bottom of one of the rods just for kicks though.
My unit is a used $4 Cenco 87208 5000v spectrum tube power supply. It was originally used to power various tubes for spectrometer testing. I actually got a free heart defibrillator testing machine with it to. All for less than five bucks!
For another $5 I got a spectrum tube for it!
I got this as a cheap $5.00 add-on amazon prime item!I hooked it to the Cenco power supply. It glows purplish and is awesome! The instructions that came with it say 5000v at around 10mA is good. You should only run it for about 30 seconds!I misplaced my tube holders that came with my power supply so I just soldered two wires to the end caps.I used a variac to supply power to the cenco power supply and the tube lights up at around 3-5 out of 10 on the variac knob. I had to be extremely careful unwrapping it: the instructions are wrapped around the tube and there is a glass nipple-spike sticking out the side that is super easy to break! Also, the center section is very thin and can break when you're pushing it into a tube holder fitting.
And here is the sherbet-orange helium tube I also got.
Here it is hooked up to my huge voltage divider (so it doesn't melt my multimeter). The deal was even better: it's putting out 6000 volts! There were two cords: wall plug and a remote power switch. I cut off the remote switch wires and closed the hole in the wiring by just joining two wires together.
This is a wire frame for holding folders in a file cabinet. I had two.
Now they're the rods for my Jacob's Ladder!
Here's the whole simple setup: direct attachment of the rods: no dangerous wires to melt. I kept adjusting and straightening the rods using the safe high voltage method: unplug the power supply and always have the plug in my left hand behind my back while working on the device. Some devices have capacitors in them that can store deadly electrical charges for months, even after you unplug them! This unit doesn't (I looked). I also powered it up repeatedly and watched the voltage fall on shutdown: very quick, thus a few seconds after shutdown it's dead. Although the rods can get really hot from the spark.
Here's the transformer: only 5000 volts, which is enough for a Jacob's Ladder. The sound of even this low power, yet still lethal, transformer induced a fascinating noise that suits sounds like musical wind chimes.
Thinner rods might vibrate more and create louder "music" along with the stereotypical monster movie zapping noises.
The hardest part of this project was working up the courage to s flip the power switch on.
It was so scary we forgot to turn the camera sideways! Meow!
So You Want To See Alpha Particles With Your Eyes PART 5
Visually, this is the most boring way to see alpha particles (or their impact on the physical world at least) in my series. It's also the easiest and cheapest. Unlike my previous 4 posts on this subject, there will be no need for: high voltage; dry ice; Geiger-Mueller tubes or even simple phosphors slopped onto a glass slide.
Nope! All this project takes is any old cheap webcam-and source of alpha radiation. You'll also need a desktop computer to run the webcam with, and a couple screwdrivers.
At my local Disabled American Vets resale shop (kind of like the Salvation Army shops) they have a big box of webcams for .99 cents each! In previous posts I pried the IR filter off of one to make an infrared camera. This time we're prying off the lens in addition to the IR filter.
The steps were simple: take out the screws of the casing. Rip off the lens bezel. Unscrew the lens completely out.
Here's where webcams differ: some have the IR filter as the last part of the lens: the end that is normally inside the camera. Hold the lens at different angles and if you can see green/red coatings that's probably the IR filter. If not, there will be a teeny-tiny little greenish piece of glass inside the camera that used to nearly touch the inside end of the camera. Anytime I've ever taken a webcam apart this filter has always just fell out for me. Sometimes you'll have to pry it out.
Next, all you do is set it up in a dark container and lay an alpha particle source onto the CCD chip of the camera: BOOM! You'll get little white and blue dots zinging all over. Lift off the alpha source and no more moving spots or specs.
I experimented many times, placing and removing the alpha radiation source and starting at my computer screen. The dots disappear when the alpha source is removed. A couple times they did not come back--it turns out I had the alpha source (I have many) flipped around the wrong way: flip it face down onto the CCD and the moving dots returned.
Here's a video showing radiation on and off: I edited down, but the results were the same for dozens of tests: radiation shows up as white and blue dots zinging around. Removing the radiation results in no dots. Placing radiation sources upside down showed no-greatly reduced amounts of dots.
The results are similar to my alpha sphinthariscope only I don't have to wait 10 minutes for my eyes to adjust to darkness-and I don't have to shove my eye inches away from a pile of radioactive material! Let the webcam get blasted in the face with radiation.
The mesmorizing waves of dots and dashes looks like the surface of a lake at night during a full moon in the sphinthariscope, in my webcam alpha particle detector it's more hit or miss. The moon reflected in a small puddle.
The webcam's CCD is way more high-tech than the sphinthariscope though.
CCD stands for "Charge-Coupled Device" and are the sensor that "sees" in many webcams. These pure silicon dioxide is used to change photos to electrons. Light to digital information. Many times these are "doped" with other chemicals to give the silicon dioxide a better affinity for certain inputs. There are different types of dopants, but webcams use "P" dope, which can use our friends from the last post: indium and gallium! Those two help snatch infrared light.
In my last post I mentioned the super lattice of eutectic alloys. There is a similar theory in CCDs where the crystal lattice is missing a component and this empty spot grabs electrons and helps move them around over and over again as a charge carrier. The 'hole' moves all around as the electrons keep moving to file the hole, which leaves a new hole.
This is actually the function of MOSFET and MOS transisistors: like a quantum bug-zapper waiting for photons. Then they carry this info down to the actually CCD which just digitizes this information. So really, the MOSFETs do the interesting work of "seeing".
OK hole, slide me toward the CCD!
A couple more times and then the Meowfet will dump it's charge to the CCD and then it's sent to a pixel!
The term eutectic should not have any other meaning than
"fusible at a low melting point"
-The Engineering and Mining Journal (1903)
Gallium is a neat metal. It will melt in your hand! Magicians use it mold spoons, then they swirl the spoon in a glass of hot water and the spoon melts in front of the audience's eyes!
It takes a while of holding it to get it to melt in your hand. Once melted it stays a silvery metallic liquid for a while. It looks like liquid mercury.
If you bend a piece of gallium it makes a crackling sound. It "cries" when you bend it. Just like tin and indium do. It has to do with the crystalline structure of the metal "twinning" and breaking and then grating and vibrating against each other. If you keep bending you can break these metals-in which case you can melt them and let them re-solidify. Then you can bend them and make them cry all over again.
If you take some liquid gallium and put it onto a soda can, on the seam of the opening drinking hole, it will eat through the aluminum and pop open the can for you (after a while). Gallium embrittles steel and aluminum by forcing it's way (diffusing) into their grain lattice. A pretty cool way to open a pop can!
If you found a piece of gallium on a table you'd think it was a piece of lead or cooled solder. At least until it started melting in your hand. In certain applications gallium is a replacement for mercury in thermometers.
Indium is less interesting at first glance. It also "cries" if you bend it. It also looks like a piece of lead or cooled solder. To melt it you can use a blow torch and it'll turn to a liquid very easily, only to cool and solidify quickly. Okay, you'd think you'd have a huge blob of solder. Indium is used in some types of solder actually.
Sometimes indium is used to reduce the amount of mercury in dental fillings. Kind of boring huh?
Well, if you lightly rub a piece of gallium against a piece of indium THEY TURN INTO A LIQUID METAL ALLOY THAT STAYS A LIQUID! I tried it myself:
It was totally cool and really messy. I put the liquid into a glass container: mistake! This mixture "wets" glass, which means it coats it very thinly and gives it a tinted look. What good is that? Well it's how touch screens for tablets and phones are made and how newer solar panels are being produced!
A reason to care about relatively warm melting points? Liquid metal telescope mirrors! If you fill a container with a liquid and spin it, the liquid will have a low point in the center and raise up at the sides. This forms a parabloid shape that can be used as a telescope. It only has to spin at around 8 revolutions per minute-nice and easy.
[Our old nemesis Isaac Newton took credit for figuring this trick out. He had trouble spinning his container at a stable rate, so he didn't use it for telescopes.]
Of course a telescope mirror (even made of liquid metal) also has to be shiny. Mercury is used for this, but is toxic so gallium/indium liquid metal alloys are a great replacement. It's way cheaper to get a spinning vat of this liquid metal than to cast a HUGE glass mirror in a HUGE oven, grind it with tools to the curved shape, coat it with a reflective surface coating (usually aluminum) and then polish to 1/8 of a wavelength.
Of course you can tilt and swing a regular mirror telescope all around--can't really do that with a vat of liquid metal spinning around. You can look straight up with it really well though!
Looking straight up-like me! Meow.
The best place to have a telescope boringly aimed straight up would probably be at the equator. It's warm there too so the gallium indium mix would be fine and liquid.
A telescope like this at either pole might freeze...or would it? I guess that's were the "Melting Point Controversy" rears it's ugly head. I have no intent on freezing while staring at the North Star 24/7 so again, I don't care about that. Build that thing at the equator and it'll sit and spin as the stars curve by all night long. Just look carefully, because once something zings by you can't tilt a liquid telescope to follow it!
This new liquid alloy I created by rubbing gallium and indium together is referred to as a eutectic alloy. Many people mention "eutectic" liquid metal alloy in reference to any liquid metal, but eutectic refers to a mix of solid ingredients that melt at a single temperature together all at once, instead of at two different temperatures and the percentage of the elements mixed allows for the lowest melting point of those two materials possible**.
So, I wanted to find out if my blob of liquid alloy was actually also eutectic. Research was in order!
[If you liked the liquid metal blob and want to make your own, just hit Ebay or Amazon right now and forgot the oddness that follows below.]
**I APPARENTLY HAVE NO IDEA WHAT EUTECTIC MEANS...AND I'M NOT ALONE:
I thought I understood, but was amazed by the variety of definitions that have arisen in different fields of industry and science. So feel free to just breeze past the following:
Of course if you're manufacturing thermometers or ultra-high tech sensors or touch screens with this material its actual melting point at your usage's pressure and temperature may be quite important.
A bucket filled with cheese and hunks of steel could be heated and cheese would melt at a different temperature than the steel. Even 5lbs of butter and 1 molecule of steel would result in the butter melting at a way, way lower temperature than the steel. At the melting point of steel the butter will be melted too; however it wouldn't be uniform: the butter would melt before the steel, not with it, and varying the proportions of butter vs steel wouldn't really affect the "alloy" of butter and steel. The same thing as it cooled: the butter and steel would harden at different times/temperatures. The cheese and steel would never fuse either. A lot of non-technical dictionaries and encyclopedias say that "eutectic" just means the mixture with the lowest melting point possible. In that case a single molecule of steel and a bunch of butter would have the lowest possible melting point mixture of butter and steel...but that's true of pretty much anything, so I'm going to go out on a limb and say that ButtSteelium is NOTeutectic. It doesn't melt as a WHOLE entity-the butter melts and then later at a higher temperature the steel melts (even if it's just a single flimsy molecule of steel).
You don't get a eutectic mixture by throwing random things into a bucket and melting them together eventually. Although I've read were this is referred to as a "Simple Eutectic System" or "Simple Eutectic"...did they just mean a "binary alloy".Are they using the old meaning "easily fusible"? Would they consider ButtSteelium eutectic? Although simple eutectic refers solidifying points and to me at least, seems to mean differing points of solidifying for the components. I've read fruit juice freezing into a popsicle being called a simple eutectic: one liquid (fruit juice) freezing into two solids (ice and slushy water vs. juice). Seems the opposite of eutectic. Hmmm...I'll keep trying to understand...
The definitions I've found all seem to conflict with each other (solidifying at different times doesn't seem eutectic, or does it?). The confusion? Eutectic reaction is used to refer to easily fusing of ingredients that turn to a liquid. Eutectic point refers to that special, lowest temperature where everything liquefies as a whole.
Indium and gallium rubbed together are both a liquid at the same (room) temperature--which is all I was interested in. If you vary the percentages of indium and gallium you can make them liquefy (or solidfy) at the lowest temperature possible for indium and gallium.
For commercial eutectic mixtures of gallium and indium you usually add some tin (and sometimes some bismuth)! Even this is a subject of controversy. It's a liquid, and under the brand name "Galinstan®" it seems to have percentages of these (and more) elements and a much lower melting point than other gallium, indium and tin (stannum) eutectic alloys.
The company that owns Galinstan® (Geratherm Medical AG) markets it with a very low melting point-other people say generic versions made by other companies have a much higher melting point even though (it is thought) that they all have very similar percentages of ingredients.
A few wisely point out that eutectic mixtures of TWO metals are defined as having the lowest melting point possible when the mixture melts as a whole, which is achieved by varying the percentages of those TWO metals. Binary (two) ingredients have a "sharp" melting point.
Others mention a requirement that: the mixed alloy has a melting point lower than either of the ingredients by themselves. This is radically different than just having the percentage mixture of ingredients that melt together at a lowest temperature for that percentage mixture.
Welders and solderers use eutectic to mean: this alloy melts completely at an exact temperature. Non-eutectic alloys melt in a range of temperature as it heats up one ingredient melts faster and the alloy turns into a mushy paste as the ingredients are acting on their own, instead of as a whole, fused eutectic thing. For welders: eutectic means the ingredients all turn to a liquid at a single temperature. Non-eutectic means some of the ingredients start liquefying while others don't yet so you get mushy, paste-like, jelly glop called a slurry...which can be useful. When looking at eutectic alloys, welders look at how stuff melts, most scientists look at how stuff solidifies.
One can speak of the eutectic point of salt water. Add more and more salt and the water can get colder and colder before freezing. Many refer to this as "lowering the eutectic of water" which means that melting point of the water is the same as the salt dissolved into it? They'll solidify at the same time? Well, I guess when you're below the normal freezing point the salt water would turn to sludge (non-eutectic) and then freeze solid. Yeah, maybe?!?! They mean the freezing point is lowered. More on this in the second bullet point below.
"EUTECTIC" ACCORDING TO VARIOUS SOURCES:
"Many mixtures of materials crystallize into two distinct materials when they solidify. First one component forms, then the other. A system of this sort is called a simple eutectic." Seems backwards no? One THEN the other? Does this contradict "as a non-eutectic mixture cools, each mixture's component will solidify at a distinct temperature, until all material is solid."
A mixture where both elements solidify at the same time/temperature (which is the 'V' point of a typical phase diagram from school). Even in school cooling was boring, it was the super lattice instant full meltdown mode that was neato! OK, that sounds like the eutectic point of saltwater again.
On top of these two definitions there are these that I've found in use. So, is a eutectic alloy:
The lowest possible temperature of solidification of a mix of ingredients? (Eutectiod).
The lowest possible temperature of melting of a mix of ingredients? (Eutectic).
Eutectiod is the lowest temperature phase change (freeze or melt)?
Lowest melting point of a mix of two ingredients possible (due to percentages of each in the mix)?
The mix has a lower melting point than either of the ingredients in it do alone?
Both items in the mix melt at the same time?
Both items in the mix solidify at the same time?
The ingredients fuse upon freezing or melting?
The ingredients form a super lattice?
Any liquid metal or liquid metal alloy?
Pretty much any two things melted or fused together like ButtSteelium?
A mix that melts and freezes at a single temperature that the lowest melting point of any mixture of the same ingredients in different percentages and the melting point is lower than either of the ingredients by themselves?
A solid mix that forms a super lattice structure which instantly releases both ingredients that melt at the same temperature and time?
The lowest uniform melting point of a mixture?
A mixture that doesn't have a slurry phase (ie. no slow freeze or melt)?
The point or mixture in which the solidus and liquidus are the SAME?
A liquid freezes into two ingredients at the same time/temperature and not a range of temperatures?
These definitions encompass: eutectic, eutectic system, simple eutectic, eutectiod, eutectic temperature, eutectic point or points, eutectic transformations and/or solder specification.
Hmmm...for any definition I disagree with or that contradicts another I can find multiple "reliable" sources. These sources are college professors, technical data sheets, various shop manuals, manufacturer specs, sales specs and a whole lotta "I use eutectic item xyz everyday in my laboratory/welding shop/space station/etc. and it doesn't mean this but means that..."
I really don't care about all this, but I do find it interesting. For me in this instance: gallium and indium rubbed together becomes a liquid before your eyes. That is cool. That is fun. So yes, I have the luxury of enjoying liquid metal alloys without needing to know if they're 'truly' eutectic.
That was boring so I made a bunny out of cotton balls. It will be delicious! Meow.
