Would a guitar amp built with these sound like a tube amp?
The Vacuum Transistor: A Device Made of Nothing
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Re: The Vacuum Transistor: A Device Made of Nothing
#12Regarding the opening anecdote - some have suggested the Soviets used vacuum tubes so that their planes would survive the electromagnetic pulse from a nuclear explosion.
Re: The Vacuum Transistor: A Device Made of Nothing
#13I'm surprised the IEEE editors allowed the word "Introducing" in the title. Vacuum FETs are often a target of the diamond thin-film community. (Diamond has a very interesting electronegativity: Very little energy is required to get an electron out of diamond and into the "vacuum" (usually air.))
The problem is with carbon in general is it has a band gap 5x larger then Silicon. Which overall (but not entirely) means if you want to build a transistor with Diamond (or graphene) you need to put 5x as much voltage into it. The reason graphene is great for transistors is with its higher band energy its 5x harder for it to soft set itself. So if we pretend todays 11nm transistors have a 1% chance of electron tunnel…
> The problem is with carbon in general is it has a band gap 5x larger then Silicon. Which overall (but not entirely) means if you want to build a transistor with Diamond (or graphene) you need to put 5x as much voltage into it.
I should have said electron affinity rather than electronegativity: You're not trying to get electrons from the valence band into the vacuum, just from the conduction band to the vacuum. Diamond actually has a negative electron affinity, which is why the vacuum electronic folks were excited about it.
Re: The Vacuum Transistor: A Device Made of Nothing
#14Regarding the opening anecdote - some have suggested the Soviets used vacuum tubes so that their planes would survive the electromagnetic pulse from a nuclear explosion.
> Regarding the opening anecdote - some have suggested the Soviets used vacuum tubes so that their planes would survive the electromagnetic pulse from a nuclear explosion.
I don't think the authors delved too hard into the history. I interviewed at General Dynamics in Ft Worth around 1986: They told us that they they just designed out the last of the tubes on the F16 and were working to remove the last tubes from the F4U Phantom.
Nobody mentioned that the tubes were around as a countermeasure to EMP; it was more about waiting for technologies to mature to the point that you'd believe they were battle-tested enough for your most advanced weaponry.
Edit: The above anecdote in reference to the article claiming
> By the mid-1970s, the only vacuum tubes you could find in Western electronics were hidden away in certain kinds of specialized equipment
Re: The Vacuum Transistor: A Device Made of Nothing
#15Regarding the opening anecdote - some have suggested the Soviets used vacuum tubes so that their planes would survive the electromagnetic pulse from a nuclear explosion.
Which the end of the article mentioned.
Re: The Vacuum Transistor: A Device Made of Nothing
#16I'm surprised the IEEE editors allowed the word "Introducing" in the title. Vacuum FETs are often a target of the diamond thin-film community. (Diamond has a very interesting electronegativity: Very little energy is required to get an electron out of diamond and into the "vacuum" (usually air.))
I don't understand - why not "introducing" - it seemed to be an introductory level article on the topic of "vacuum transistors"?
I guess that was the correct interpretation and why the IEEE editors allowed it. They did mention that they did not introduce the architecture (which is what it sounded like originally) about midway through the article.
Re: The Vacuum Transistor: A Device Made of Nothing
#17I'm no scientographer, but it seems to me that a dependence on helium may be a stumbling point for getting cheap vacuum transistors to the market. The ongoing helium shortage[1] is driving the price of helium up which could make helium-based vacuum transistors expensive, limiting widespread adoption. It could be that high-speed helium vacuum transistors become a speciality product for those projects that feel the need justifies the additional cost.
[1] http://www.decodedscience.com/helium-shortage-situation-upda...
Re: The Vacuum Transistor: A Device Made of Nothing
#18Would a guitar amp built with these sound like a tube amp?
I thing it gets digitized at some point, so it would probably lose the analog sound of a tube amp.
Re: The Vacuum Transistor: A Device Made of Nothing
#19Regarding the opening anecdote - some have suggested the Soviets used vacuum tubes so that their planes would survive the electromagnetic pulse from a nuclear explosion.
DISCLAIMER: This is what I remember once hearing in an ECE class. I was hesitant to post this comment given that it might be garbage, but perhaps someone can help confirm or disprove this.
I once heard that one of the reasons the Soviets continued to use analog systems was that they were "faster, more compact, and more power efficient" [than a digital computer]. This came at the cost of flexibility. For example, an op-amp allegedly can do integration faster and with less power than a digital computer, but the IC can't be reprogrammed. Digital computers have huge benefits, but ones that come at a cost.
Thoughts/input anyone? As I said, I might be completely off base so please nobody take that as anything more than "food for though".
Re: The Vacuum Transistor: A Device Made of Nothing
#20I'm no scientographer, but it seems to me that a dependence on helium may be a stumbling point for getting cheap vacuum transistors to the market. The ongoing helium shortage[1] is driving the price of helium up which could make helium-based vacuum transistors expensive, limiting widespread adoption. It could be that high-speed helium vacuum transistors become a speciality product for those projects that feel the nee…
If I understand the basic premise, then other mostly stable and abundant gases (like Nitrogen, or even air) could probably be used as well, if the transistor size and voltage are small enough. (That's wholly conjecture, though. I also am not a sciencer).