Back to the future - new vacuum tube production - Page 1
Forum section: electronics / general

author: PaulAm
author_rank: Frequent Contributor
timestamp: March 25, 2022, 04:12:20 pm
content: Western Electric seems to be exploring expanding vacuum tube production. They currently manufacture the 300b, a $700 four pin triode (introduced in 1938) but they're also looking at making other types for audio and guitar amp use, possibly at a somewhat lower price point..https://www.westernelectric.com/blog/expandThere was also an article on the local news last night on expanding production of vinyl record production equipment.What's next? Shag carpeting?

author: PartialDischarge
author_rank: Super Contributor
timestamp: March 25, 2022, 04:32:42 pm
content: Quote from: PaulAm on March 25, 2022, 04:12:20 pmTaking pictures with film and wasting the time and money to develop them

author: daqq
author_rank: Super Contributor
timestamp: March 25, 2022, 04:33:01 pm
content: See:https://www.daliborfarny.com/Yeah, people are making tubes again. For niche markets, but still awesome.

author: james_s
author_rank: Super Contributor
timestamp: March 25, 2022, 05:33:27 pm
content: Quote from: PaulAm on March 25, 2022, 04:12:20 pmShag carpeting will come back into fashion sooner or later, most things do. I actually quite like it, reminds me of my grandmother's house when I was a kid, probably wouldn't put it in my house due to practical reasons though.Vinyl record sales have been higher recently than in many years, about half the music I buy today is on vinyl. Analog photography is making a comeback, some people are seeing the value in owning a physical possession rather than just a collection of bits. Vacuum tubes are neat and never really went away, I'm happy to see production increasing although I'm certainly not the target market for a $700 tube.

author: TimFox
author_rank: Super Contributor
timestamp: March 25, 2022, 05:37:03 pm
content: With respect to film: I use large-format sheet film on 4x5 inch and 8x10 inch view cameras.On a beautiful summer morning, I was photographing a cityscape near the Wrigley Building at the Chicago River with my (huge) 8x10 monorail camera, when a tourist stopped to chat and he asked me how many megapixels I had.I did a quick mental calculation, and replied "roughly 500". Checking later, using the specifications on Kodak E100G transparency film and the resolution on my lens, I found that I was reasonably close.

author: james_s
author_rank: Super Contributor
timestamp: March 25, 2022, 05:40:40 pm
content: My brother is into photography and has several medium format cameras, he's done some impressive work.I use film primarily for radiography, I have a digital sensor (dental) that is handy for taking a quick look at something but film is dramatically higher resolution. Using mammo or industrial film I can image the bond wires inside SC-70 and other tiny IC packages. The problem is I have no way to digitize the resulting image that can even come close to reproducing what is on the film.

author: TimFox
author_rank: Super Contributor
timestamp: March 25, 2022, 05:55:06 pm
content: At an SPIE meeting I attended, a Swedish group had produced an impressive high-resolution x-ray detector, using microlithography techniques to fabricate a gas ionization detector with very small cells. They were targeting this device on x-ray mammography, which requires high spatial resolution. With the small cells, it was practicable to operate the device in counting mode, rather than measuring the output current. They pointed out that the statistical noise at low doses was less obtrusive in counting mode than the electronic and dark-current noise in a current-mode detector. To demonstrate the performance, they presented images of fish with very fine bones.After the presentation, one member of the audience stood and said that was the best example of "Poisson imaging" that he had ever seen.Half of the audience laughed. My boss, sitting next to me, missed the joke.

author: james_s
author_rank: Super Contributor
timestamp: March 25, 2022, 06:17:09 pm
content: That sounds impressive. Unfortunately something like that is going to be way, way outside of my hobby budget. I was lucky to acquire the dental sensor which is an older model. I'd like to have a larger flat panel detector but even used ones typically cost thousands. Film is a bit of a hassle but it's cheap and effective.

author: BrokenYugo
author_rank: Super Contributor
timestamp: March 25, 2022, 07:04:03 pm
content: I suspect this is driven by one of the major suppliers of tubes, new and NOS, being out of the market for the foreseeable future.

author: PaulAm
author_rank: Frequent Contributor
timestamp: March 25, 2022, 07:26:29 pm
content: Yes, you can clearly hear their wailing and gnashing of teeth with the supply cutoff.Apparently Western Electric have been thinking about this for a while, well before the crisis, and can produce 7 and 9 pin as well as octal tubes without starting from scratch (although it still requires a production ramp up). It will be interesting to watch.Big crisis = big opportunity? Interesting times.

author: Bassman59
author_rank: Super Contributor
timestamp: March 26, 2022, 06:24:49 pm
content: Quote from: PaulAm on March 25, 2022, 04:12:20 pmIt's worth noting that this "Western Electric" company is not the old Bell Telephone equipment manufacturing arm. They bought the rights to use the name.That said, there will always be a demand for vacuum tubes for musical instrument use. That demand isn't small, either. I'd love to see a US-based manufacturer of the standard tubes found in guitar amps. I have an Ampeg V4 waiting for new power tubes (7027A) and my knowledgable friends say the current offerings (JJ) all kinda suck.

author: Bud
author_rank: Super Contributor
timestamp: March 26, 2022, 06:38:39 pm
content: Quote from: PartialDischarge on March 25, 2022, 04:32:42 pmIt was a lot of fun and was educational. I'd do it again with a blink of an eye.

author: 3roomlab
author_rank: Frequent Contributor
timestamp: March 26, 2022, 06:59:21 pm
content: this guy is still around

author: PartialDischarge
author_rank: Super Contributor
timestamp: March 26, 2022, 10:44:27 pm
content: Quote from: Bud on March 26, 2022, 06:38:39 pmYep, actually I’m going back to onionskin and FeCl3 to manufacture my own PCBs, so fun and educational

author: james_s
author_rank: Super Contributor
timestamp: March 27, 2022, 08:48:00 pm
content: Quote from: PartialDischarge on March 26, 2022, 10:44:27 pmI still etch my own PCBs now and then, it is fun, and when I need something simple like an adapter or quick prototype I can have it in an hour instead of a couple of weeks. I develop my own B&W film occasionally too, this summer I'm planning on building a darkroom for my brother in his basement, he's much more into photography than I am. I also baked a loaf of bread the other day, despite the fact that there's a whole shelf of it down the street at the supermarket.

author: LaserSteve
author_rank: Super Contributor
timestamp: March 29, 2022, 05:50:46 pm
content: The secret is placing the order for the needed specialized glass from Schott or Corning or Techniglas before the yearly extrusion melt. Otherwise you can spend a whole year looking for the sealing glass with the right expansion. If you do find it, you will pay through the nose for individual four foot sticks instead of cases.Getters are a whole different story in difficult to obtain unless you are buying industrial production quanities.Steve

author: georges80
author_rank: Frequent Contributor
timestamp: March 29, 2022, 08:25:20 pm
content: Some pics from my last trip to china with a stop at the SEG market of course. This was Dec 2019... as covid was starting its attack...cheers,george.

author: cdev
author_rank: Super Contributor
timestamp: March 29, 2022, 08:39:30 pm
content: NASA has for some time been manufacturing some small vacuum tubes (I think they are ceramic actually) for use in some space related electronics applications. heir form factor is small, more like solid state devices than tubes..

author: PartialDischarge
author_rank: Super Contributor
timestamp: March 29, 2022, 09:03:25 pm
content: To switch high voltage for some tests I do use thyratrons, otherwise I’d have to use a stack of thyristors which is more complex

author: RJSV
author_rank: Super Contributor
timestamp: March 30, 2022, 05:56:57 am
content: ? How far down can a Lab shrink the Vac Tube dimensions ?Maybe, a Nano-machine scale device could fill some need, perhaps for Giga-Hz power device (in comm Satellite). ?

author: RJSV
author_rank: Super Contributor
timestamp: March 30, 2022, 06:02:57 am
content: (oops, meant to also say)Perhaps the cathode heater type filament can be replaced by some alternate 'emission' causing mechanism, when on nano-scale?Like, just a RAW electric field, causing electron emission...Or, a laser actuated emission, then modulated the traditional way...I.E. with grid between Cathode and electron receiving plate. ?

author: Zoli
author_rank: Frequent Contributor
timestamp: March 30, 2022, 07:05:50 am
content: Quote from: RJHayward on March 30, 2022, 06:02:57 amSome 15-20 years ago was a promising(and very efficiently killed) display technology, called(IIRC) Surface Emitting Device. The working was by emitting electrons on short range(10-100µm, IIRC), which were hitting phosphorous layers for light emitting.It was expected to replace the plasma displays, having the same or better color reproduction fidelity. Those electron emitters were based on (ordered)carbon nanotubes, emitting on room temperature, without vacuum.The patents are about to expire/expired, so if anybody want to dig(I don't), happy digging, and let us know the results.

author: daqq
author_rank: Super Contributor
timestamp: March 30, 2022, 08:13:10 am
content: Quote from: RJHayward on March 30, 2022, 05:56:57 amThe conventional tubes:https://korgnutube.com/en/https://www.thevalvepage.com/valvetek/Nuvistor/nuvistor.htmStrange concepts using vacuum tube like concepts:https://en.wikipedia.org/wiki/Nanoscale_vacuum-channel_transistor