is it possible to buy individual transistors that are in a vacuum tube form factor
@typhlosion hmm not that I know of... the electrical behavior of tubes is different than that of transistors, so they aren't drop-in replacements. but I wonder if a solid state vacuum tube replacement (with multiple components) is possible...
@rey it's not for drop-in replacement so much as "it would be funny to build a computer in a similar form factor but more reliable and with less power draw"
@typhlosion that would be a lot of transistor-tubes! but it sure would be neat
@rey @typhlosion I know there are solid state relays available lol
@rey @typhlosion actually!!! there are solid state devices that work almost identically to vacuum tubes!! they're called static induction transistors, SITs, and they're extremely uncommon and i don't know if any have ever been made as commercial products. (i should ask our boss, he did stuff with them when he worked at microsemi) they're basically weirdly-designed JFETs that exhibit a kind of punchthrough that's basically identical to vacuum tube behaviour, just at lower voltages
-F
@typhlosion there's at least one i've found with a cursory search, replacing a 12AX7 vacuum tube for amplifiers, but something like a Fetron (a whole line of solid state vacuum tube substitutes) is a niche product that hasn't been in production in a long time
[1] https://en.wikipedia.org/wiki/Fetron
[2] https://www.onlypedals.com/AMT-Electronics-12AX7-Warm-Stone-LE-solid-state-vacuum-tube
@typhlosion One argument against it is that the durability of vacuum tube sockets was never very good, and it's recommended to not be plugging and unplugging even the modern production tubes. You can certainly pack your transistors into that amount of space, but you're just introducing new issues with a tube connector instead of the standard pins on the board or the little pins to solder
@typhlosion: You could just place the individual transistors a bit apart, and perhaps even place nice LEDs next to them to show their states.
A catch, though: the best-known family of classic transistor-based logic, TTL, relies on multi-emitter or multi-collector transistors. These are really easy to make if you're designing a silicon chip yourself, but they have little use as discrete components, and availability may be quite an issue. As a result, homebrew CPUs tend to go for either MOSFET logic, which can be more cumbersome to work with because discrete MOSFETs are rather static-sensitive, and/or build on things such as quad NAND gate chips rather than entirely discrete parts.
@typhlosion: No, you'd have to make the adaptor boards yourself.
When transistors came, backwards compatibility with vacuum tubes wasn't seen as a big issue. There weren't powerful lobbying groups hyping thermionic valves as their Legacy(tm). And, well, transistors behave in significantly different ways from valves that it didn't make sense to just try to fit them into the same pinouts, the way that new logic family chips often reuse pinouts from previous logic families.
@typhlosion the opposite existed (called nuvistors) but i'm not sure if what you want was eve rmade
-F
context: i was watching the latest veritasium video (https://www.youtube.com/watch?v=FU_YFpfDqqA) and someone in it said something to the effect of "the advantage of having a processor that's a meter tall is that you can point to individual parts of the processor"
so my thought is, you could make a board that Looks Like a vacuum tube computer, for demonstration purposes, but which doesn't actually rely on power-hungry and failure-prone vacuum tube triodes to function