has anyone tried to make a vacuum tube in space? - Page 1
Forum section: electronics / projects

author: coppercone2
author_rank: Super Contributor
timestamp: September 25, 2024, 02:00:42 am
content: Has anyone tried to make a vacuum tube in space?I always wondered if old sci-fi is correct with the big old style computers.If you brought an assortment of different wires into space, along with a spot welder, it seems that you could make very high quality vacuum tubes in a "glove box" that opens into the outside environment. Especially in a deep space environment. It seems that you can POSSIBLY make different types of wires out of elements you find in asteroids in stuff. It would be very easy to fix tubes.Trying to bring all the equipment to make a flying fab seems pretty ludicrous in comparison.The hardest requirement, for a vacuum source, goes away.and you could have circuits on the outside of the ship that are without enclosure. Behind the structural shield but in front of the environmental seal. They could be fixed with a EVA mission.Then you can classify spares by how many spares you can make in total, instead of how many spares of each circuit you need. You can even make a little foot powered coil winding machine and glass lathe loland with burnt out tubes, you could actually do nearly 100% recycling. A small amount might get vaporized but almost all of the tube will remain intact. You can melt it in a induction furnace and make new wire, after scraping off any coatings. It is almost like hanging your laundry outside to dry...Another idea that it gave me is that you could have a reduced pressure 0 gravity work area that is like a balloon that is weakly pressurized with air. IT would not have enough air to breath, but you could use a small backpack compressor to provide you with breathable air. So long you have power to run it, you will not run out of air. I mean like big. No air tanks needed to work nearly outside on building structural stuff in a low oxygen environment. Like repairing a solar array. And if you lose parts it would be contained inside of the 'tank'. Low chance of fire there.

author: TimFox
author_rank: Super Contributor
timestamp: September 25, 2024, 03:07:24 am
content: I always thought that a great synchrotron particle accelerator could be built on the moon with a huge radius for the path but no vacuum container required.

author: coppercone2
author_rank: Super Contributor
timestamp: September 25, 2024, 03:22:14 am
content: that too, it seems ridiculous to do terrestrial vacuum experiments compared to how good it is up there lol

author: ejeffrey
author_rank: Super Contributor
timestamp: September 25, 2024, 03:50:11 am
content: From what I have heard, the vacuum,inside a satellite chassis isn't that great. Unless you build it like a UHV system there is still outgassing and in the free molecular flow regime there is a limit to how fast you can pump those particles out no matter how good the vacuum is outside.

author: coppercone2
author_rank: Super Contributor
timestamp: September 25, 2024, 03:59:40 am
content: is this perhaps a problem with making things out of aluminum?Sat chassis loves adhesives tapes etc. their built like a cheap laptop IMO

author: Andy Chee
author_rank: Super Contributor
timestamp: September 25, 2024, 06:31:05 am
content: Quote from: coppercone2 on September 25, 2024, 02:00:42 amThat's not the hardest requirement of vacuum tube manufacturing.The big problem with anything in space, is the cost of launching raw materials/fuel into orbit. This is not an unknown quantity, it is calculated relatively easily with GCSE/high school level physics.

author: Phil1977
author_rank: Frequent Contributor
timestamp: September 25, 2024, 06:35:21 am
content: I´ve seen in a video that some of the former CRT manufacturers brought space down to earth to do R&D on open CRTs .They´ve build huge vacuum chambers and a poor employee (or do some people want this job??) had to work there in something very similar to a spacesuit.I suppose during construction of the vacuum chambers some people also have thought about moving the test station into orbit

author: coppercone2
author_rank: Super Contributor
timestamp: September 25, 2024, 07:32:03 am
content: Quote from: Andy Chee on September 25, 2024, 06:31:05 amtry launching a fab into orbit to maintain a deep space mission!

author: tszaboo
author_rank: Super Contributor
timestamp: September 25, 2024, 07:55:24 am
content: Quote from: TimFox on September 25, 2024, 03:07:24 amVacuum isn't the most difficult part of the LHC. I was visiting it this summer. It uses about 200 MW power, and about 80% of that goes to cooling. And despite the fact that the Moon has vacuum on it, it's temperature is nowhere near what a superconductor needs to work. So suddenly you need to cool a lot of magnets on the Moon without atmospere, that you also have to ship there somehow. And it has the detector, which is 7000 metric tons heavy that you would need to duplicate on the moon. The weight of it is so much you would need 500 Saturn V launches to send it to the Moon. And that's just the detector, excluding the magnets.So on the Moon it's a bit less noisy, because people don't live there. And that's it.

author: Jeroen3
author_rank: Super Contributor
timestamp: September 25, 2024, 08:22:28 am
content: I would assume the moon, without it's atmosphere and magnetic field, is a terrible place for a detector of a LHC.Background radiation and solar winds and such...You'd also need to ship a tunnel boring machine?Machining in vacuum and low gravity sounds like horror to me. Lack of convection makes your tools too hot and lack of gravity makes your chips float in the way.

author: Andy Chee
author_rank: Super Contributor
timestamp: September 25, 2024, 08:35:46 am
content: Moon is a great site for a radio telescope thoughhttps://www.nasa.gov/general/lunar-crater-radio-telescope-lcrt-on-the-far-side-of-the-moon/Or a laserhttps://starwars.fandom.com/wiki/Superlaser

author: tszaboo
author_rank: Super Contributor
timestamp: September 25, 2024, 09:17:03 am
content: Quote from: Jeroen3 on September 25, 2024, 08:22:28 amYou really need to be a lunatic (pun intended) to think that we can easily replicate one of the largest man made objects in space.I mean this could be a long term goal on the time scale of centuries, but maybe first we should find better things to do first.

author: Phil1977
author_rank: Frequent Contributor
timestamp: September 25, 2024, 09:24:30 am
content: And also switching to vacuum tube electronics won't solve any outer space chip crisis. If I´d had to write a science fiction story I would assume some company builds a Focused Ion Beam (FIB) machine that builds silicon chips like a 3D-printer.Performance of modern digital chips is so far away from everything that could ever be imagined with vacuum tubes that it won't help if you just get rid of the vacuum problem. Though it sounds like a good story for the cyberpunk genreI´m not into this scene but I suppose they don't like FIB-machines that much....

author: coppercone2
author_rank: Super Contributor
timestamp: September 25, 2024, 08:41:09 pm
content: navigation computer might not need that much hardware. ion beam is complex hardware to fix millions of miles away from earth. I think its real scary to have to depend on a complex machine like that. Or a controller for a thruster, life support controller, etc.Alot of the advanced electronics is kind of 'nice to have' but its not worth dying over because you can't get a complex spare that does what you need and 500 auxiliary functions that you don't need but make life more interesting or easier.If you are a little off target because of a error from low computational power, it just takes longer, so long you know where you are and where you need to go, so long you have time its OKIt would be a transport ship, not a science vessel. And more manual work means less time for the crew to get bored of watching re-runs...

author: AnalogTodd
author_rank: Regular Contributor
timestamp: September 25, 2024, 09:18:23 pm
content: Chips that get put in those environments aren't just a single device. They are usually triple redundant so that if a single one fails you have two other backups. The biggest concerns for anything leaving Earth surface for orbit or deeper space are what get termed SWaP -- Size, Weight, and Power. Big and bulky or heavy is bad, it takes just too much fuel to get it where it needs to be. High power is bad because you don't have atmosphere to bleed excess heat to, and ultra low power can be bad as well in case things cool too far they may stop working.For the weight of the internals of a vacuum tube together with the power it takes to get the voltages to run them, you can get some serious computational power that is capable of doing a whole host of things. Granted, you make things redundant and need to deal with single event effects for any chip based solution, but those are known concerns.

author: coppercone2
author_rank: Super Contributor
timestamp: September 25, 2024, 11:38:42 pm
content: if their gonna scuttle that thing, why not try building some tubes in there? convert one of the labs into a vacuum chambermaybe one of the future astronaut can replace their shoe laces whit molybdenum wire or something and build a spot welder

author: fourfathom
author_rank: Super Contributor
timestamp: September 26, 2024, 01:33:16 am
content: When I visit the moon, I want to build a giant traveling-wave tube power amplifier for the HF frequency range, to use as an interstellar transmitter. Chicken wire would work for the elements, regular wire for the helix.

author: coppercone2
author_rank: Super Contributor
timestamp: September 26, 2024, 02:27:55 am
content: actually that might be on of the best transmitter ideas I heard for a signal that goes far. I wonder how efficent it would be.You could make spikey coils at low frequency to radiate more heat, I wonder how Q ends up working for very large circuits that are normally not built. surface finish might not be that big a deal anymoreIt says it can be around 50% efficient.

author: Randy222
author_rank: Frequent Contributor
timestamp: September 26, 2024, 02:54:41 pm
content: Quote from: ejeffrey on September 25, 2024, 03:50:11 amOf all the worries of space, wouldn't space dust be an issue? On earth the vacuum sucks out the dirt to some extent. In space, when you make a container you trap in the space dust?

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: September 26, 2024, 07:19:32 pm
content: Don't know about a vacuum tube but it seems like a great environment for a light bulb.