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Ask Slashdot: How Do You Build Your Own Vacuum Tubes? 275

Could you beat wireless headphones by creating your own DIY home audio system? Two weeks ago one Slashdot commenter argued, "to have good audio that is truly yours and something to be proud of, you need to make your own vacuum tube amplifier and then use it to power real electrostatic headphones over a wire." And now long-time Slashdot reader mallyn is stepping up to the challenge: I want to try to make my own vacuum tubes. Is there anyone here who has tried DIY vacuum tubes (or valves, to you Europeans)? I need help getting started -- how to put together the vacuum plumbing system; how to make a glass lathe; what metals to use for the elements (grid, plate, etc). If this is not the correct forum, can anyone please gently shove me into the correct direction? It needs to be online as my physical location (Bellingham, Washington) is too far away from the university labs where this type of work is likely to be done.
Slashdot's covered the "tubes vs. transistors" debate before, but has anyone actually tried to homebrew their own? Leave your best answers in the comments. How do you build your own vacuum tubes?
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Ask Slashdot: How Do You Build Your Own Vacuum Tubes?

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  • Covered in the past. (Score:5, Informative)

    by Pikoro ( 844299 ) <initNO@SPAMinit.sh> on Sunday September 18, 2016 @06:37PM (#52914105) Homepage Journal

    Here's a good one with links to more: http://hackaday.com/2016/05/04... [hackaday.com]

    • by Pikoro ( 844299 ) <initNO@SPAMinit.sh> on Sunday September 18, 2016 @06:38PM (#52914109) Homepage Journal

      And here's another: http://hackaday.com/2014/11/21... [hackaday.com]

  • No no no. (Score:5, Interesting)

    by fyngyrz ( 762201 ) on Sunday September 18, 2016 @06:39PM (#52914121) Homepage Journal

    You don't need vacuum tubes. That's such a horrible audio myth. They glow in the dark and look nice. Aside from that, they produce more distortion, more noise, use more power, are more fragile, and have shorter lifetimes than solid state electronics. They do not sound better, given $X spent on whatever, presuming some reasonable amount of tech is returned per dollar.

    OTOH, if you just want to make vacuum tubes because.... you want to make vacuum tunes... have at it :)

    • Re: (Score:2, Informative)

      by Anonymous Coward
      The reason real guitarists prefer tubes is because of the distortion. Solid state just doesn't compare.
      • Re:No no no. (Score:4, Interesting)

        by Bruce Perens ( 3872 ) <bruce@perens.com> on Sunday September 18, 2016 @08:23PM (#52914497) Homepage Journal

        Of course, modern solid state amplifiers aren't particularly power limited (at least if you have the cash) and should never be driven into distortion. Effects pedals give you whatever distortion you want and have the advantage that you can turn the amplifier some level other than 11 and you still have the distortion you like.

        • Re:No no no. (Score:5, Informative)

          by BlueStrat ( 756137 ) on Sunday September 18, 2016 @10:50PM (#52914951)

          Of course, modern solid state amplifiers aren't particularly power limited (at least if you have the cash) and should never be driven into distortion. Effects pedals give you whatever distortion you want and have the advantage that you can turn the amplifier some level other than 11 and you still have the distortion you like.

          As a pro-level guitarist for 4+ decades and who also has been designing & building tube guitar amplifiers for nearly as long, I have to disagree.

          Distortion type effects pedals are attempts to imitate what goes on in a tube guitar amplifier being pushed to (and past) it's limits and some come close (and many more close enough for the average local artist/band in bar/small-gig venues) but it does not sound nor 'feel' the same to play through for a good guitar player.

          Nearly all the flagship lines of the major guitar amplifier manufacturers are tube amps. Most pro-level concert/festival guitar amplifier backlines are tube amplifiers. Fender Twin Reverbs, Super Reverbs, and Marshall amplifiers (often vintage '60s/'70s era) are the vast majority of venue-owned backline kit provided for touring acts (and usually specified by the artist/band in the performance contract 'riders' section) at most large venues.

          As to making a home-brew vacuum tube, it is doable but not practical. To get predictable performance mechanical tolerances must be exacting and the materials used in commercial tubes are rather exotic and difficult (if not impossible to come close to) for a home-brew vacuum tube maker. What you end up doing is making a tube using 'best guesses' and test/measure the tube's operational parameters and design the circuit around those parameters, rather than the other way around.

          The other problem with the inability to make tubes with fairly consistent and predictable performance and operational parameters is that it makes building things like the typical push-pull 2 or 4 tube Class AB1/AB2 power amplifier extremely difficult, as the tubes must be fairly close in there operational parameters or the unbalanced circuit will likely destroy the tube(s) of one side that conduct the most current. It would also be necessary to custom-wind output transformers to whatever plate impedance the tube(s) happened to exhibit

          If you love vacuum tubes and spending exorbitant amounts of time & money mucking about with molten glass and exotic metals for fun, have at it. Just don't expect to build the equivalent of a McIntosh MC30 or a 100-watt Marshall using them.

          There is an amazing amount of exacting engineering, sophisticated manufacturing processes/techniques, and exotic materials science in the old commercial vacuum tubes even by today's standards and is pretty much impractical and beyond the means for the vast majority of private experimenters to reproduce in a home shop.

          Strat

          • Re:No no no. (Score:5, Informative)

            by Solandri ( 704621 ) on Monday September 19, 2016 @06:03AM (#52915859)
            This whole thing reminds me of the filters people have come up with to modify digital photos to simulate different types of film [prime-junta.net]
          • by Zontar_Thing_From_Ve ( 949321 ) on Monday September 19, 2016 @07:17AM (#52916027)
            You said:

            As to making a home-brew vacuum tube, it is doable but not practical. To get predictable performance mechanical tolerances must be exacting and the materials used in commercial tubes are rather exotic and difficult (if not impossible to come close to) for a home-brew vacuum tube maker. What you end up doing is making a tube using 'best guesses' and test/measure the tube's operational parameters and design the circuit around those parameters, rather than the other way around.

            There is an amazing amount of exacting engineering, sophisticated manufacturing processes/techniques, and exotic materials science in the old commercial vacuum tubes even by today's standards and is pretty much impractical and beyond the means for the vast majority of private experimenters to reproduce in a home shop.

            Strat

            I've lived long enough to know that when some dude says "I want to build my own vacuum tubes" that he's not interested in hearing how unrealistic it is.

      • Re:No no no. (Score:5, Interesting)

        by TechyImmigrant ( 175943 ) on Sunday September 18, 2016 @09:23PM (#52914715) Homepage Journal

        The reason real guitarists prefer tubes is because of the distortion. Solid state just doesn't compare.

        Well these days they do compare. Humans can't distinguish between an amp modeled on (for example) a Kemper modeling amp and the tube amp it modeled.
        A few years ago it was not the case, but DSP always wins in the end.

        • As a former guitarist, i can tell you this: is not so much about the sound, but how tube amps react to ones playing. The old Line 6 stuff, f.ex, already sounded fantastic on recordings back in 1999 but didn't quite "feel" like the real thing.

          Having said that: i haven't tried the latest state-of-the-art offerings from Kemper et al, but i hear this has improved a lot since then.

    • Re: (Score:2, Funny)

      by Anonymous Coward

      But but but... you obviously haven't listened to hand crafted artisanal vacuum tubes using hand blown glass and mastodon hair wrapped with isometrically pure tungsten. The tungsten caresses the electrons in a way that's just not possible modern day transistors.

    • by DewDude ( 537374 )

      they produce more distortion

      Only in circuits where they are driven extremely hard...or guitar amps where a tube will naturally do what takes ton of DSP

      more noise

      again...depends on what type of circuit you're using and if you're using the suitable tube. Stick a 6AU6 in your audio stage and it's going to get noisy.

      use more power

      You have me here. Thermionic Emission requires the heat.

      are more fragile

      Toss-Up. Drop a tube and it'll likely break depending how and what it hits. On the flipside; there are ways a transistor will fail that a tube won't care about. My tubes aren't goi

      • Re:No no no. (Score:5, Informative)

        by Anonymous Coward on Sunday September 18, 2016 @07:22PM (#52914309)

        You cannot measure or quantify sound quality.

        Yes you can. Hi-Fi equipment is suppose to *reproduce* the original as accurately as possible. This is something you can and people do measure. Hence the name Hi-Fi an abbreviation of High Fidelity.

        • This is better stated as "most people don't know what good sound reproduction actually sounds like". We certainly can measure sound quality. People like Amar Bose didn't ever publish specifications because the average listener prefers unreal bass (go listen to a live orchestra) and isn't too sensitive to distortion.

          It gets worse with digital. We took a medium that could reproduce sound much better, and compressed it, taking away that advantage. All musical compression is designed to replace aliasing with no

      • Because tubes have to heat the cathode in order to eject electrons, at audio frequencies the best tubes are inherently more noisy than the best transistors. It's not a lot of noise - in a properly designed circuit it's unlikely to be noticeable - but physics does not allow a tube at audio frequencies to be as quiet as a transistor.
      • Sure you can, unless you believe in magic.

        If the output waveforms are the same when plotted on an oscilloscope, then there is no difference between the amplifiers as far as sound quality is concerned.

      • In my youthful years of building valve-audio, with the faithful Mullard book, the biggest issue was usually mains hum. Rectifying heater current was not a total solution, and the big AC around seemed to jump any gaps however careful the wiring. Anyone remember 'humdingers'? Does the best valve kit nowadays really not hum when no-input is turned to full volume?
    • Re:No no no. (Score:5, Informative)

      by KingOfBLASH ( 620432 ) on Sunday September 18, 2016 @07:04PM (#52914223) Journal

      Actually that's not true, just ask a guitarist (and IAAG - I Am A Guitarist!)

      Vacuum tubes create a noisy signal, but in a weird coincidence, they do it in a way that is pleasing to the ear. The clipping and distortion sounds "warm," and there's an added depth in the sound (harmonics) that you don't get via transistors -- unless you create circuits that mimic the behavior of a vacuum tube.

      Metallica? Tube amps. John Mayer? Tube Amps. Clapton? Tube amps. BB King? Tube amps. Eric Johnson? Steve Vai? Garth Brooks? All tube amps.

      Of course, much of the "tone" we guitarists revere comes from overdriven and abused guitar tubes -- cranking up the volume on the tube so that there's massive distortion and noise -- which again sounds pleasing to some people.

      Now, it's one thing to overdrive a tube or change the bias on it to get a particular sound from your guitar, what about building a tube amp to just listen to music?

      Well, I suspect this is essentially "remixing" songs. Adding a bit more depth, dirt, or warmth (from the noisy tube) might sound better but that's subjective, and it's all about personal preference.

      So, sir, you might argue that you dislike what a noisy tube does to your signal, but you can't say some people won't perceive it as improved, as it's about personal taste.

      • Re:No no no. (Score:4, Interesting)

        by thegarbz ( 1787294 ) on Sunday September 18, 2016 @08:04PM (#52914427)

        You're conflating two different purposes for an amplifier. An instrument amplifier is part of the instrument itself. The choice of that amplifier has a significance to the music that is trying to be produced. Implying that all those famous guitarists chose tube amps because they are better at something ignores all the solid state amps that are used by musicians too. They have a different sound, not good, not bad, just different. Both when run normally and when overdriven. The choice of an instrument amplifier is purely artistic.

        Well, I suspect this is essentially "remixing" songs. Adding a bit more depth, dirt, or warmth (from the noisy tube) might sound better but that's subjective, and it's all about personal preference.

        This irks me. It's like saying that the Mona Lisa is nice and all but it should have been painted with more yellow. The purpose of a hifi amplifier is to reproduce the small signal as faithfully as possible, and with as little distortion as possible. Every design aspect should be based on the output being nothing more than a larger input, any modification to the signal should have happened before this stage (either in the studio, or if you really feel like not listening to the music as the musician intended then with a pre-amp). In that regard an interesting combination is often a vacuum preamp followed by a solid state tube amp.

        But really the parent was on the money with the physics behind it. Tubes produce a more pleasing sound than a typical Class AB push pull amplifier due to harmonic distortion being predominantly odd order rather than the even order in solid state amplifiers. However in terms of being able to faithfully reproduce a signal in a larger form they are blown away in every metric (except power consumption, the GP got that wrong) buy a well designed Class A solid-state amplifier.

        Now personally I think the Mona Lisa is too small.

        • I got that backwards. Tubes produce even-order distortion. Push-pull solid state amplifiers have almost zero even order distortion.

          Read twice, post once.

          • Just think of it as even harmonics, and it fits better into musical theory.

            Obviously, what you really want to do is use amplifiers with sufficient power that they are never driven into distortion. And if you want distortion, get it from an effects pedal.

        • This irks me. It's like saying that the Mona Lisa is nice and all but it should have been painted with more yellow.

          ::SNIP::

          Now personally I think the Mona Lisa is too small.

          The way art is presented (whether that's music through a hi fi stereo or a painting to the public) can change the way the art itself is perceived.

          You might have no control over how much yellow Leonardo used for Mona, or how big he painted her, but you might put her under fluorescent or halogen lamps, or in sunlight (which will all add slightly different color casts to the painting). You might choose to display her behind a fresnel lens to make her bigger. Or you might put her on a white wall, or a black w

        • The purpose of a hifi amplifier is to reproduce the small signal as faithfully as possible, and with as little distortion as possible.

          Yes but...

          I mean I agree and all, but older music often sounds better on old and objectively worse kit than newer music on the same kit. I think the reason for that is you simply couldn't make high power high linearity amplifiers cheaply until relatively recently, and musicians knew that mostly their music would be listened to on the kit of the day, so they wrote and mixe

      • by MrKaos ( 858439 )

        Actually that's not true, just ask a guitarist (and IAAG - I Am A Guitarist!)

        Vacuum tubes create a noisy signal, but in a weird coincidence, they do it in a way that is pleasing to the ear. The clipping and distortion sounds "warm," and there's an added depth in the sound (harmonics) that you don't get via transistors....So, sir, you might argue that you dislike what a noisy tube does to your signal, but you can't say some people won't perceive it as improved, as it's about personal taste.

        IAAP and Vacuum amps add a 'third harmonic distortion' to an input signal. Whilst this is desirable for a guitarist, for home listening it introduces distortion that I did not intend to be there when I produced your excellent performance. All that time I spent adjusting the attack and release on the compression to capture those really cool movements of your fingers on the strings are lost because a 'audiophile' decided that they knew better that the people who produced the music in the first place.

        Transis

        • by hughk ( 248126 )

          I think the new class D amps eliminate even this issue, however they use more electricity.

          It should be the reverse. Class A uses the most power (~20% efficient), Class AB about 60% and D comes in a little under 100% (~90%) or so because the semiconductors are acting as switches dissipating very little heat. The downside is that the high frequency switching can induce all manner of interference which will cause havoc if not properly dealt with.

    • Not true. [idc-online.com] Breakup characteristics are measurably different between tubes and transistors.

      • Doesn't matter. No modern amplifier has to be driven into distortion. We've got all of the power you need.
    • Re: (Score:3, Insightful)

      by Anonymous Coward

      Spoken as someone who knows a little, but not enough about music engineering.

      Tubes have been and are still used for ALL manner of instruments (including vocal) for "warming" sounds, saturation and creating distortion effects. The even harmonic distortion they produce when you overdrive are pleasing to the ear and can add an organic character to a recording that is otherwise lacking.
      Different tubes produce different sounds so experimenting with your own would be interesting. For example: I remember replacin

      • Instrument is the right word. But there's a key theory in your post:

        In music it is quite often the IMPRECISION that makes the bland great.

        That imprecision is an artistic choice. It should not be a listener's choice. The imprecision of instrument amplifiers are part of the instrument. The goal of a normal stereo amplifier should be the most precise reproduction of the artist's choices.

        But I'm probably in the minority with this view given how many times I step into a hired car and find the first thing I need to do is drop the bass and treble back down to zero.

    • by Khyber ( 864651 )

      "and have shorter lifetimes than solid state electronics."

      Spoken like someone that never used W-grade (military) tubes in their life. Mine are still kicking in my 1978 Fender Super Reverb, from when my father bought them. That's almost 40 years. You got any solid state stuff that old, gramps?

      • You're not using the original capacitors, are you? If so, some time with an ESR meter and the required replacements would help.

        Yes, I definitely have solid-state electronics that old. Including test equipment. But most have been recapped.

    • You don't need vacuum tubes. That's such a horrible audio myth

      The summary doesn't say anything about sound quality. My guess is that he's using vacuum tubes because it's possible to 100% DIY a vacuum tube amplifier from off the shelf parts. If you try to build a solid state amp from scratch, you are probably going to need to get custom PCBs built and you'll get to test the steadiness of your hands as you try to solder tiny SMD chips.

      Now, making the actual tubes seems a little overkill (is he also making his own transformers, resistors, wiring, etc?) but, if you want

      • Having done both, it's much easier to build a solid state amp than a tube amp from scratch. Neither requires a PCB, but tubes almost always have to be socketed and usually need a chassis. If the signal level is low. the filament voltage either needs to be DC or needs to be shielded from the signal path. Transistors and ICs don't have filaments. ICs provide more gain per stage, and a power amp can be made with just 1 or 2 ICs, depending on the gain required. Tube amps require an output transformer. Tubes use
    • Vacuum tubes don't necessarily sound more accurate , but unless you run a recording studio you don't necessarily want accurate , which is why studio monitors don't necessarily make for good listening speakers. Valves however sound good and that's a result of their behaviour at high current. Transistor amplification hard clips at max power creating flat peaks that sound absolutely terrible, whereas Valves produce rounded clips with a degree of compression at the peaks. This has the psychoacoustic effect of

    • ... they produce more distortion... They do not sound better, given $X spent on whatever, presuming some reasonable amount of tech is returned per dollar.

      This is simply not true; in fact, it's a line of BS almost as bad as the one that says thousand dollar cables will make your system sound magical. (BTW, something you hear is not necessarily true just because it's said by a bunch of engineers bathed in the fountain of 'knowledge' passed on by an earlier generation of engineers whose conclusions were 'helped' by marketing requirements).

      First, let's look at the metric known as THD; it is calculated as the ratio between the total power of all harmonics and the

    • more distortion

      Metal fans consider that a feature, not a bug.

    • by Mashiki ( 184564 )

      and have shorter lifetimes than solid state electronics.

      Going to dispute that one based on my own personal experience. I have a 1925 radio(can't remember who it was made by), beautiful piece of work. Maple case, cherry wood veneer, it is of course all tubes(mix of amplified tubes and non-amped), uses lead solder, has the wiring diagram on the back of the case written in pencil, the person putting it together was smart enough to use wire colours in particular orders and is signed by the person who built it. That in itself is unusual, since a lot of the people

    • A lot of old technology works better than the new stuff. However you will need to be an expert at it to get it that way.
      For example the adjustable focus on camera vs the auto focus. Pros use the adjustable focus so they capture the picture just as they want it. For the average person who gets the same camera they will be taking a lot of blurry pictures with an expensive camera. And would be taking better pictures with an auto focus camera.
      The same with tubes. A pro can make them sound warm and clear, wh

  • This may well be overkill for your needs, and it's a bit pricey, but the book Building Scientific Apparatus [amazon.com] has been on my wish list for a while. It has chapters on working with glass, vacuum technoloy, charged-particle optics, and electronics, among others.

    Sigh, too many projects (including a pair of novels to finish) and not enough time.

    • by tsotha ( 720379 )
      I love that first link, but I notice he doesn't include a getter, which would reduce the life of his tubes. The second guy uses getters that still have some life from broken tubes..
  • The vacuum pump that will give you the high vacuum so they won't burn out before you can blink is the problem.
    you'll need a diffusion pump as a second stage to a regular pump
    something like this
    http://www.instructables.com/i... [instructables.com]
    You will also have to coat the interior of the tube with some sort of getter to keep the vacuum.
    and then there are the seals
  • Other than the experience points, I can't see why you'd make your own tubes. Would you make your own transistors?

    I've hand-wound guitar pickups and made a ribbon microphone from scratch. Fun stuff, but I could never approach the quality of a stock Fender pickup or Royer ribbon mic.

    Sovtek still imports Rusdian tubes, right?

    k.

    • Would you make your own transistors?

      Yes. If I could.

      Humans pride themselves on learning a skill. Providing this skill is within reach and doesn't require super expensive industrial equipment why wouldn't you attempt to build something yourself?

      Some people buy pre-made equipment.
      Some people assemble equipment from pre-made modules.
      Some people assemble modules using components and manufactured circuit boards.
      Some people make their own circuit boards.

      The rabbit hole is only limited by your ability to make something that is functionally suitable,

      • Would you make your own transistors?

        Yes. If I could.

        What is stopping you is that you think you need ultrapurification and microscale fabrication. No. Remember that the first receiving diodes were semiconductors, and while some used germanium it was not unusual to just use a rusty razor blade and the graphite point of a pencil. There are lots of semiconductor materials available to you, and making a cat's whisker is not difficult. It won't be the best transistor in the world, but it will amplify.

    • You can find practically any tube you might be looking for on Amazon.com, if you know the part number. Many of the same tubes you can find on the specialty sites that serve audio fetishists who "roll tubes" in their single-ended triode tube amps can be found for half the price on Amazon.

    • by tsotha ( 720379 )

      I think people make tubes because a normal person can with some combination of money and effort - used vacuum pumps aren't that hard to rebuild. You could cheap out and use fixtures, but a reasonable quality glass lathe is something like $14k. It would be a relatively expensive hobby, but still cheaper than cars.

  • Of course, physics and engineering labs used to "make their own" vacuum tubes. But generally, they had skilled glass blowers on hand who could create vacuum-proof glassware for them. If you really want to try, you might consider starting with chemical glassware intended to be used with vacuums.

  • The difference between tubes and transistors only surfaces when you're overdriving them. Transistors clip, tubes go non-linear. Buy an amp designed for the power you need, and this will never be an issue.

    -jcr

  • Get the requisite materials. Then find a rocket. Launch into space. Open up the pod bay doors. Let the vacuum in. Then assemble. Done!
  • Does it make it sound warmer? Is it warmer than these wooden standoffs ( 600.00 each ) I got to hold my oxygen-free digital cables off the floor ( a steal at 900 for 6ft )?

  • Various rock musicians prefer tube amplifiers because the conventional tube circuits used since the 1950's, when driven far into distortion, emit even harmonics much more than odd harmonics. This is a perceptually more comfortable sound to the music listener.

    Older transistor circuits (we're talking the 1970's) tended to emit odd harmonics.

    Obviously you can make a transistor circuit that distorts with even harmonics. However, it is much better to use an amplifier of sufficient power that it is not driven int

    • If you want distortion, use an effects pedal. Don't get it from your amplifier.

      I'll pit my Dr. Z against your effects pedal anyday

    • In RF amplifiers, the harmonics are filtered out. The transistors themselves are not particularly linear.
    • by hey! ( 33014 )

      Sure but 1.3 KW is not "tremendous" power -- it's amateur range stuff. Broadcast AM stations go up to around 50kw, which is a "normal" for that application.

      In the 30s and 40s, WLW in Nashville broadcast at 500KW. Radio Monte Carlo's transmitters currently put out 2x700KW in long wave and an even 1MW in medium wave. Russia's Taldom transmitter pumps out 2.5MW in long wave.

      So I'd say anything over 10^8 watts is tremendous.

      There are tubes that individually are rated in the MW range, like the 8974 power te

  • ...some people spend more time playing with their HiFi than listening to it.

  • Electrostatic speakers/phones aren't especially hard to make, but sourcing the materials can be difficult. You need ultra thin polyester film for the diaphragms, and some sort of weakly conductive coating (Licron or similar antistatic spray works well). You also need a method of stretching the diaphragm film tight and then gluing it while stretched. I invented a pneumatic stretcher almost 30 years ago when I was into all this stuff. 4693H contact adhesive will stick to the polyester (not much else will)

  • Claude Paillard [claude.free.fr] has a great video [dailymotion.com] showing how it's done (and photos here [claude.free.fr]). He's built not just his own vacuum tubes but also most of the tools needed [claude.free.fr] to do so. So if you want to build your own molecular pump you'll find data here [claude.free.fr].
  • It's possible to do, but you'll need a fair bit of gear and expect your first few batches to be defective or die soon after powering up.

    There are lots of youtube videos that show how it's done, but many of them leave out critical bits of info. As a project in tech school my lab partner and I built a working vacuum tube (we all had to), but we had all the gear we needed and lots of instruction. Even then it was difficult to get t right, lots of failures and lots of "sort-of-working" tubes.

    So it can be done,

  • A vacuum tube is a lightbulb with extra electrodes. So he is a video of how to make a light bulb with glass. https://m.youtube.com/watch?v=... [youtube.com]

  • I make tubes! (Score:5, Informative)

    by Doctorglasseye ( 4714055 ) on Monday September 19, 2016 @04:43AM (#52915701)
    Howdy all, I'm a scientific glassblower (25 years now), and I make my own tubes. I'm at www.incandescentsculpture.com; not much tube info there yet -been a few years in beta mode on them, but some other high-vacuum delights are to be seen. (My handmade incandescent bulbs, my Tesla wireless brush bulbs, the 'fuxie' tube....) Even the production of a simple, low-mu triode is non-trivial; the requisite equipment and knowledge take years to acquire, and a page long essay to even enumerate. OP, I'd be glad to help; perhaps we can compose a FAQ and parts list for kindred spirits.
  • I want to give making my own valves a go, but first I've got to overhaul my vacuum pump, because it doesn't suck. (Well, I need at least 35torr, and it has trouble getting to 120torr.)
    I've got this book and like it: Instruments of Amplification [amazon.co.uk].
    It's not so much a howto guide as a recounting of "I did this, and this is how it worked". Useful tips on how to cut open bulbs and harvest filaments, how to drill glass, basics of vacuum working and lots else.

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