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Hand-Made Vacuum Tubes
djmoore writes "Over at Make Magazine, watch this video of a French amateur radio operator making and testing his own vacuum tubes. It looks like he built much of his own equipment as well. The Make poster notes: 'I love the ease with which he performs these rather high-end skills (like glass forming), the gestural flourishes (like it's hand magic), and the Zelig-esque soundtrack.'"
Over at Make Magazine, watch this video of a French amateur radio operator making and testing his own vacuum tubes.
This was covered in Make Magazine, primarily because Nature abhors a vacuum.
The theory of relativity doesn't work right in Arkansas.
Make Magazine sucks? How dare you!
Engineering is the art of compromise.
This guy isn't just a tinkerer, but an artist as well. This kind of thing is an art as much as it is a science.
While vacumn tubes are strictly in the realm of hobbyists and zealous audiophiles, nevertheless it is important for teens and young adults to understand where the electronics industry started from. They're already made to study what can argueably be considered useless information, so why not study something that is cool and informative as well? Think of it as shop class for nerds.
Feed the need: Digitaladdiction.net
Perhaps we can use these hand-made tubes to make a new hand-made internets! Think of the possibilities!
Neither Make nor Slashdot have the basic decency to name the man: Claude Paillard.
What is it with acting like foreign nationals are some sort of trained monkey? C'mon folks.
Anyway, here's a direct link to his site so you can skip the non-article at Make. Site includes much information (use the fish as needed), the streaming dailymotion vid, and a download link for those who can't see streams. Enjoy.
http://paillard.claude.free.fr/
Thanks Claude! That rocks.
for pointing out the man's website and giving him direct credit. Its sad to see something placed without naming the inventor.
Not Million Electron Volts, but
"Male Enhancer Volume System Product"
How much juice/oomph can YOUR tubes deliver?
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
For better or not, you don't need to be a zealous audiophile to appreciate the sound of a tube guitar amp.
Why do you have to see everything through the category useful/useless? Is it so hard for you to imagine that one day, let's say in the next 1000's of years, we will need a guy who can make vacuum tubes? It's never good for any technologies to be lost, even if they seem too old to be useful now.
The only thing that would make this cooler is if he made his own Nixie tubes!
I thought there were issues not addressed clearly in the video. First, I thought I learned in college chemistry (now rummaging in decades-old longterm storage media) that one of the big problems was getting a good seal of glass around metal, which wasn't solved until they put together the right glass with the right metal.
Also, aren't the electrodes in a vacuum tube coated with something to prevent early breakdown? And isn't there some chemical you have to put inside the tube to absorb the gas given off when electrons smash into the electrodes? So while this is incredibly neat-looking, I don't think the tubes would last very long...
--Rob
Towards the Singularity.
he also made all the necessary equipment, like vacuum pump. If you are interested in tubes, he says the "musée des arts et métiers" is a reference. This is an engeneering museum in Paris, which has an incredible collection. When I go there, I stay for hours. Do not mistake it with the science, the nature science, or the technology museum (which are also quite interesting).
Oh yeah? Well, I built a wheel out of popcicle sticks!
Table-ized A.I.
My kids and I built a crystal set and made a cats whisker diode for it using some brass sheet, wire and a lump of galena (from the mineral & crystal shop). Also made a diode with a rusty razor blade and another with a lump of silicon. These didn't work as well as shop germanium diodes, but they still worked. Made our own variable capacitors using paper and tin foil too.
You can even build simple amplifiers etc using tunnel diodes: http://home.earthlink.net/~lenyr/ntype-nr.htm
Engineering is the art of compromise.
It will also serve to bring us back after the collapse of society and technology.
Id like to see you make semiconductor based transistors in your basement.
---- Booth was a patriot ----
If you look closely at the wires he is sealing into the glass "press", you will see a short reddish-brown section. This is most likely "dumet", or copper coated nickel/iron. This material is specially designed to have the same coefficient of thermal expansion as glass, and was used as the sealing material in most receiving tubes. The copper coating forms an oxide layer that dissolves into the glass, creating a vacuum-tight seal.
Before the development of dumet, kovar, and other specialized alloys, the seals in very early tubes were made using platinum wire. Cost considerations brought this to a quick end, as soon as cheaper suitable materials were developed.
The electrodes in later tubes were often coated with various materials to aid heat dissipation or reduce secondary electron emission. Early tubes that were similar in construction to what is being made here generally used plain metal grids and plates.
Most tubes contained a "getter" made of barium or other reactive metal, to adsorb any gas molecules which survived initial pumpdown, or which were liberated from the internal elements during operation.
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The silvering has nothing to do with radiation. It is a thin coating of reactive metal to take up any oxygen left in the tube after it has been sealed. If you ever find an old tube where the silver patch has gone white, it is gassy and will not work properly. (It may work to some degree but is also likely to have a strange glow from ionising the gas. Depends how much gas has leaked in.)
You do get X-rays from tubes working at high voltages, but they are of pretty low energy in typical applications and probably don't make it out through the glass. TV tubes use leaded glass to reduce the X-radiation.
If you wanted to build some part of an embedded device that absolutely had to take some really ugly conditions, you could do a whole lot worse than to build that specific module using valves. Let's say you wanted to build a new module for the IIS, for example. The internal circuits can largely be protected, so conventional radiation-proof chips would be fine. However, if you wanted reliable computing elements that could be strapped to the outside of the pod, you've harsh conditions indeed. Lead-smothered rad-hardened silicon chips that can handle space tolerances and have their own heating elements would probably work. Lots of things that can go wrong, though. Complexity-wise and weight-wise you're probably not significantly better off than using thermionic valves with none of the extras.
Where else could valves be used? Easy. If the cathode and anode are deliberately mis-aligned, then one or more grids must be set to a value such that the directed power completes the circuit. If something goes wrong (too much power, something fails, whatever), then the beam is either not pushed at all or pushed far too far. In either case, you've an all-electronic circuit-breaker - ideal if you want to get rid of fuseboxes and mechanical trip-switches.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
The purpose of using vacuum tubes in a guitar amp is for the overdrive characteristics. When overdriven, solid state amplification circuitry clips the waveform to the voltage rails, resulting in a harsh sounding distortion due to the dissonant overtones.
A tube amp driven to distortion compresses the waveform rather than hard clipping. This results in a waveform rich in harmonic overtones - the classic distorted guitar sound.
Any person who is not tone deaf can tell the difference between solid state distortion and tube distortion. Please don't compare the basic principles of rock guitar with overpriced audiophile folly.
I do have to say this is one of the most impressive projects of its type I've ever seen; it's clearly a labor of both love and skill.
Brackets contain world's first nanosig, highly magnified:[.]
vacuum tubes.
Once you get beyond the crude PN junction diode (like a galena crystal), making transistors and such requires ridiculously pure germanium and/or silicon. These materials are purified by a process called "zone refining" which uses induction heating to melt the semiconductor materials at incredibly high temperatures. Induction heating in turn requires many kilowatts of radio frequency power, which is exactly the type of application where vacuum tubes are still widely used even today.
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Especially when it's one of these played through one of these.
The 'silvering' in most tubes isn't a screen but is caused by a process called 'gettering' where a small amount of a magnesium or calcium-based compound is burnt off (evaporated) by an external induction coil as part of the final manufacturing process. As the valve is 'gettered', the magnesium/calcium 'cleans out' any small traces of gas left in the envelope.
AT&ROFLMAO
take that homebrew computer club! i'll bet none of those guys ever made their own transistors!
when religion is no longer the opiate of the masses, governments will resort to real opiates.
maybe now I can make my own interwebs!
We came,we saw, we kicked it's ass!
You can learn a hell of a lot from vacuum tubes! They are far easier to understand than transistors.
There's a reason why they're called "valves" in the UK. It's like a valve controlling a powerful stream of water; a small change on the valve leads to a very large change of current. That change in current can, in turn, control a much bigger valve that controls an even larger current.
In this case, the "valve" is a control grid (that spiral thing) surrounding the cathode (the thin hot wire in the middle). The big cylinder is the "plate". The cathode itself has a cloud of electrons around it (because it's hot), and a small signal on the grid controls how much of that can scoot across to the plate (which is positively charged due to a power supply putting a strong positive voltage on it). So a weak sine wave signal on the plate will lead to a big sine wave current from the plate.
There, now you know the basics of amplification (although I skipped some details). I couldn't have done it by describing a BJT (transistor), because they're far weirder.
How about instead we push for the Flash source code to be opened up?
If it's gonna 'take over' the Internet, it should be an open standard. I should be able to build the Flash Player the same way I build Seamonkey.
Freedom amateur radio operator...
There, fixed it for you.
not because you need wheels, but because you need inventors." Not sure who first said that.
Oh, yeah, it's not easy to pad these out to 120 characters.
ah ha! you are so right!, i have my nose in the HF too much, i mostly ignore VHF/UHF except when programming a police scanner...
i have a nice R.L. Drake shortwave receiver and love to listen to HF a lot, so when ham radio is the topic the HF bands are what i automatically think of...
Politics is Treachery, Religion is Brainwashing
You can learn a hell of a lot from vacuum tubes! They are far easier to understand than transistors.
For someone studying electronics, I agree. But as a general subject? Why not teach the theory on how they used to slop pigs 100 years ago? Or the techniques for cutting hair? Or pick your esoteric piece of knowledge that is utterly useless to 99% of students.
Sometimes it's best to just let stupid people be stupid.
The pressure is not really that great 1Atm is about 14 pounds per square inch, with a cylinder and hemispherical shape you can withstand incredible pressures, you just cannot have any weak spots.
Bicycle tyres are inflated to up to 80 pounds per square inch.
A submarine has to undergo far greater pressures, even though the air is kept at say 1 Atm internally the pressure underwater goes up by 1Atm per 10m depth so the pressure at say 915m depth would be 1316 pounds per square inch! (record manned sub with full crew 1968)
He was superheating the entire structure to drive out occluded gases from the metal components. During this operation, the entire tube was surrounded by a coil driven by an induction heater, which was heating the plate and grid red hot, as well. All this takes place while the tube is attached to the vacuum pump, prior to sealoff.
I am not sure what material he was using for his filament wire, but if it was thoriated tungsten, then the "hot shot" cycle also serves to build up a surface layer of thorium oxide on the filament, and reduce it to metallic thorium. Thorium has a much lower work function than pure tungsten, and will emit electrons efficiently at a much lower operating temperature.
Yes, I am a tube geek...:) Years ago, I made a much cruder triode in a peanut butter jar as a HS physics project.
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you wouldn't have asked. that glow is vacuum. good old vacuum.
gas-filled tubes typically flash over as the gas starts conducting, typically violet for argon, bright yellow for hydrogen. because of the flashover point at some voltage, gas tubes are generally trigger tubes or voltage regulators.
glass in CRTs typically is thick enough to withstand tons and tons of atmospheric pressure. sometimes, they don't. that is rather spectacular, unless you are touching the glass, in which case is is amputational.
if this is supposed to be a new economy, how come they still want my old fashioned money?
"refining" a tube typically meant heating it up in an inductive system to burn out impurities and gas in the tube elements, and filaments may or may not also be heated up at that time. typically were. getters are often "flashed" with a high voltage impressed on them during this period to be sure the impurities are fully absorbed and can't get back into the tube metals and glass spacers.
many getters at the period in which that tube type he's duplicating used phosphorus. not as efficient as aluminum and barium, but easier to flash over. WWI, remember, you couldn't pull much vacuum. the getter had to do the job. so old tubes had funny colors inside from the getter flashover.
if this is supposed to be a new economy, how come they still want my old fashioned money?
, as sophisticated robotics didn't yet exist. The most sophisticated part of tube making, the assembly of the internal components or "mount" was done largely by hand, usually by rows and rows of women (smaller fingers) hunched over microscopes in dust-free rooms.
Once the mounts were assembled and welded onto the stems, the sealing into bulb and pumping down was somewhat automated. Done on a machine called a "sealex", the mounts would be inserted into bulbs, sealed in place, evacuated, heated to activate the cathodes, sealed off, and getters flashed, with each operation taking place at a different "station" on the sealex.
An interesting photo essay on the construction of the famous 300B audio triode is available here:
http://www.westernelectric.com/history/tour01.html
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He actually found a use for those tiny scissors that come with a Swiss Army Knife.
i was kidding. and i forgot to type 'hand-made $500 volume knob"
:(
i should have clicked preview
I know that tubes give a different sound. I used to work in a small recording studio, (well, specializing in making demo tapes, rather than professional recordings) One of the bass amps (can't remember brand/model, sorry) had a switch for either solid state or vacuum tube distortion (and it's no simulation or filter, there are real vacuum tubes in there)
A lot of analogue gear gives much better distortion than any new solid state stuff. a lot of old people find that digital clipping sounds terrible. (while I like it)
When i'm recording drums, I often put the mics just a little too close, record things just a little too hot, and record to tape. I move the analogue recording to my hard drive later. It makes them sound so much bigger/fuller.
With guitar, i find i could get away with recording clean electric guitar, then throw on some VST filters later to make it sound just like an effects pedal, but if they wanted that warm tube sound, no filter came close enough, I had to actually use real, physical gear.
vintage vacuum tubes are so hard to fund when they burn out, who would have though a DIY approach would be a viable option. cool!
-I only code in BASIC.-
Any person who is not tone deaf can tell the difference between solid state distortion and tube distortion. Please don't compare the basic principles of rock guitar with overpriced audiophile folly.
Much of the overpriced is going away along with tube microphonics, gassy tubes, high voltage resistors, capacitors and high power consumption. With Digital Signal Processing DSP is rapidly providing 24 bit 40KHZ or higher modeling of the classic sounds without the problems and high cost. The overdrive curve of tubes can easly be modeled in a DSP.
http://emusician.com/dsp/studio_devil_virtual_guitar_amp/
http://www.analog.com/processors/tigersharc/overview/customerstories/fractalAudio/fractalAudioIndex.html
http://www.sweetwater.com/store/detail/FM15DSP/
The truth shall set you free!
Well that's only your theory. I however believe in "intelligent distortion" (ID) and that's what I teach my kids thank you very much.
$META_SIG_JOKE
The article talks at great length about the manufacture of the CRT bulbs, and the exhaust process, both of which were easily automated, even back then. I talked about the automated "sealex" machines in my last post.
But the heart of the CRT, the electron gun, with it's tiny metal components, was still hand assembled, by operators using microscopes and tiny resistance spot welders. Just the same as standard receiving tubes. The final assembly and evacuation lent itself to automation, but the intricate assembly of the "guts" did not.
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