Well not a exactly a vacuum, they fill it with helium. "...NASA’s Ames Research Center is going back to the future with its new vacuum transistor — a nanometer-scale vacuum tube that, in early testing, has reached speeds of up to 460GHz."> https://www.extremetech.com/extreme/185027-the-vacuum-tube-strikes-back-nasas-tiny-460ghz-vacuum-transistor-that-could-one-day-replace-silicon-fetsAnd for the audiophools, > There’s no word on whether these vacuum-channel transistors will allow for the creation of small, modern audio amplifiers that sound like original tube amps — but maybe! Mikek :-)
460GHz Vacuum Transistor
Started by ●November 1, 2017
Reply by ●November 1, 20172017-11-01
amdx wrote on 11/1/2017 8:42 PM:> Well not a exactly a vacuum, they fill it with helium. > "...NASA’s Ames Research Center is going back to the future with its new > vacuum transistor — a nanometer-scale vacuum tube that, in early testing, > has reached speeds of up to 460GHz." >> https://www.extremetech.com/extreme/185027-the-vacuum-tube-strikes-back-nasas-tiny-460ghz-vacuum-transistor-that-could-one-day-replace-silicon-fets >> > > And for the audiophools, > There’s no word on whether these vacuum-channel > transistors will allow for the creation of small, modern audio amplifiers > that sound like original tube amps — but maybe!Why would anyone care if they sound like tube amps? We can get all the tube amps we want. I thought they had recreated the sound of tubes digitally, no? -- Rick C Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998
Reply by ●November 1, 20172017-11-01
On Wed, 1 Nov 2017 19:42:09 -0500, amdx <nojunk@knology.net> wrote:> Well not a exactly a vacuum, they fill it with helium. >"...NASA�s Ames Research Center is going back to the future with its new >vacuum transistor � a nanometer-scale vacuum tube that, in early >testing, has reached speeds of up to 460GHz." >> https://www.extremetech.com/extreme/185027-the-vacuum-tube-strikes-back-nasas-tiny-460ghz-vacuum-transistor-that-could-one-day-replace-silicon-fets > >And for the audiophools, > There�s no word on whether these >vacuum-channel transistors will allow for the creation of small, modern >audio amplifiers that sound like original tube amps � but maybe! > > Mikek :-) >The problem with field emission is that it destroys the tips. The e-field gradients have to be so high to rip electrons that it rips molecules too. -- John Larkin Highland Technology, Inc lunatic fringe electronics
Reply by ●November 2, 20172017-11-02
John Larkin <jjlarkin@highlandtechnology.com> wrote:> The problem with field emission is that it destroys the tips. The > e-field gradients have to be so high to rip electrons that it rips > molecules too.An extensive search of field emission showed no mention of molecules ripped from the cathode. However, numerous articles discussed cathode damage from residual ionized gasses. These bombard the cathode and destroy the single atom tips. An intriguing possibility is very close electrode spacing that allows operation in atmospheric pressure. I have come across a number of articles describing this, but cannot find any references in a brief search.
Reply by ●November 2, 20172017-11-02
On Thu, 02 Nov 2017 04:04:41 GMT, Steve Wilson <no@spam.com> wrote:>John Larkin <jjlarkin@highlandtechnology.com> wrote: > >> The problem with field emission is that it destroys the tips. The >> e-field gradients have to be so high to rip electrons that it rips >> molecules too. > >An extensive search of field emission showed no mention of molecules ripped >from the cathode. However, numerous articles discussed cathode damage from >residual ionized gasses. These bombard the cathode and destroy the single >atom tips.At high fields, atoms are ripped from a tip. I wasted a lot of time on tomographic atom probing, which does exactly that.> >An intriguing possibility is very close electrode spacing that allows >operation in atmospheric pressure. I have come across a number of articles >describing this, but cannot find any references in a brief search. >Field emitters, and field emitting triodes, have been played with for decades. A sharp tip would be an ideal point source of electrons for an electron microscope, operating in ultra-high vacuum, but the tips don't last. The compromise is to heat the tip, which really makes it a low-temperature thermionic cathode where the high field helps emission. This is one of those recurring fads like fuel cells. And more press-release fodder. -- John Larkin Highland Technology, Inc lunatic fringe electronics
Reply by ●November 2, 20172017-11-02
On a sunny day (Wed, 1 Nov 2017 19:42:09 -0500) it happened amdx <nojunk@knology.net> wrote in <otdpl7$d8u$1@dont-email.me>:> Well not a exactly a vacuum, they fill it with helium. >"...NASA’s Ames Research Center is going back to the future with its new >vacuum transistor — a nanometer-scale vacuum tube that, in early >testing, has reached speeds of up to 460GHz." >> >> https://www.extremetech.com/extreme/185027-the-vacuum-tube-strikes-back-nasas-tiny-460ghz-vacuum-transistor-that-could-one-day-replace-silicon-fets > >And for the audiophools, > There’s no word on whether these >vacuum-channel transistors will allow for the creation of small, modern >audio amplifiers that sound like original tube amps — but maybe! > > Mikek :-)With enough helium and enough transistors maybe NASA will finally rise towards the planets... Or transistors floating everywhere :-) But really it is just a trillions(tm) part of the field emission display: https://en.wikipedia.org/wiki/Field-emission_display Note the word: Non Linearity. NASA should just build HUGE THINGS like nuclear powered spacecraft that brings us through the galaxy, NASA is worse than toys-r-us. And those huge spacecraft need no shitty little non-linear fragile cosmic ray sensitive tinker toy transistors. All over for NASA SpaceX is the way to go. And Russia of course. Oh, and China. China first on mars?
Reply by ●November 2, 20172017-11-02
On Thursday, November 2, 2017 at 3:42:22 PM UTC+11, John Larkin wrote:> On Thu, 02 Nov 2017 04:04:41 GMT, Steve Wilson <no@spam.com> wrote: > > >John Larkin <jjlarkin@highlandtechnology.com> wrote: > > > >> The problem with field emission is that it destroys the tips. The > >> e-field gradients have to be so high to rip electrons that it rips > >> molecules too. > > > >An extensive search of field emission showed no mention of molecules ripped > >from the cathode. However, numerous articles discussed cathode damage from > >residual ionized gasses. These bombard the cathode and destroy the single > >atom tips. > > At high fields, atoms are ripped from a tip. I wasted a lot of time on > tomographic atom probing, which does exactly that. > > > > >An intriguing possibility is very close electrode spacing that allows > >operation in atmospheric pressure. I have come across a number of articles > >describing this, but cannot find any references in a brief search. > > > > Field emitters, and field emitting triodes, have been played with for > decades. A sharp tip would be an ideal point source of electrons for > an electron microscope, operating in ultra-high vacuum, but the tips > don't last. The compromise is to heat the tip, which really makes it a > low-temperature thermionic cathode where the high field helps > emission.Hot field emission sources last longer than cold ones. Electric arcs depend on that fact that if you get a surface hot enough under a high electric field it distorts in a way that produces a lot of very sharp spikes which are sharp enough to act as field emission tips. Hot field emission sources don't run quite that hot, but they do self-clean and self-sharpen to some extent. They aren't as stable and don't last as long as single crystal lanthanum boride source, but they are appreciably brighter, and are definitely commercially available.> This is one of those recurring fads like fuel cells.In the sense that you can buy fuel cells and field emission electron guns of the shelf. It's not so much a fad as a niche market. If John Larkin can't sell it, he sees it as a fad.> And more press-release fodder.Not to mention advertising brochures. -- Bill Sloman, Sydney
Reply by ●November 2, 20172017-11-02
On Wed, 1 Nov 2017 19:42:09 -0500, amdx <nojunk@knology.net> wrote:> Well not a exactly a vacuum, they fill it with helium. >"...NASA�s Ames Research Center is going back to the future with its new >vacuum transistor � a nanometer-scale vacuum tube that, in early >testing, has reached speeds of up to 460GHz." >> https://www.extremetech.com/extreme/185027-the-vacuum-tube-strikes-back-nasas-tiny-460ghz-vacuum-transistor-that-could-one-day-replace-silicon-fets > >And for the audiophools, > There�s no word on whether these >vacuum-channel transistors will allow for the creation of small, modern >audio amplifiers that sound like original tube amps � but maybe! > > Mikek :-) >It wouldn't work for audiophools. The noise from nearby quasi particles popping in and out of existence could be overwhelming. Regards, Boris Mohar Got Knock? - see: Viatrack Printed Circuit Designs (among other things) http://www.viatrack.ca void _-void-_ in the obvious place --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
Reply by ●November 2, 20172017-11-02
On 11/1/2017 8:44 PM, rickman wrote:> amdx wrote on 11/1/2017 8:42 PM: >> Well not a exactly a vacuum, they fill it with helium. >> "...NASA’s Ames Research Center is going back to the future with its new >> vacuum transistor — a nanometer-scale vacuum tube that, in early testing, >> has reached speeds of up to 460GHz." >>> https://www.extremetech.com/extreme/185027-the-vacuum-tube-strikes-back-nasas-tiny-460ghz-vacuum-transistor-that-could-one-day-replace-silicon-fets >>> >>> >> >> And for the audiophools, > There’s no word on whether these >> vacuum-channel >> transistors will allow for the creation of small, modern audio amplifiers >> that sound like original tube amps — but maybe! > > Why would anyone care if they sound like tube amps? We can get all the > tube amps we want. > > I thought they had recreated the sound of tubes digitally, no? >That was a bit of a joke. As I understand, in blind tests golden hears do no better than chance on A/B listening tests. The difference becomes noticeable only when over driven then the tube amps have a preferred sound over transistors. But, my ears rolloff at about 11kHz... My 20 year old daughter didn't like the 15,750hz coming from an old TV we had. Mikek
Reply by ●November 2, 20172017-11-02
