On Thu, 2 Nov 2017 09:09:59 -0500, amdx <nojunk@knology.net> wrote:>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.So you add 10dB to the transistor amp and don't do that (clip).> But, my ears rolloff at about 11kHz...Don't know about mine anymore but it would surprise me if they were that good.> My 20 year old daughter didn't like the 15,750hz coming from an old TV >we had.When I was a kid, I could walk by a house on the sidewalk and tell if there was a TV on in the house.
460GHz Vacuum Transistor
Started by ●November 1, 2017
Reply by ●November 2, 20172017-11-02
Reply by ●November 2, 20172017-11-02
On 11/2/2017 7:32 PM, krw@notreal.com wrote:> On Thu, 2 Nov 2017 09:09:59 -0500, amdx <nojunk@knology.net> wrote: > >> 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. > > So you add 10dB to the transistor amp and don't do that (clip).But that tube amp distortion is an attribute, and I'm so sorry I added that throw away line about "sound like original tube amps". Mikek
Reply by ●November 2, 20172017-11-02
On Thu, 2 Nov 2017 20:04:40 -0500, amdx <nojunk@knology.net> wrote:>On 11/2/2017 7:32 PM, krw@notreal.com wrote: >> On Thu, 2 Nov 2017 09:09:59 -0500, amdx <nojunk@knology.net> wrote: >> >>> 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. >> >> So you add 10dB to the transistor amp and don't do that (clip). > > But that tube amp distortion is an attribute, and I'm so sorry I added >that throw away line about "sound like original tube amps".For guitars, sure. For "music", no way.
Reply by ●November 3, 20172017-11-03
On Wednesday, November 1, 2017 at 9:42:22 PM UTC-7, 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. > > This is one of those recurring fads like fuel cells.Didn't someone post a link to a smartass who turned a VFD into an amplifier last time these things came up? Mark L. Fergerson
Reply by ●November 3, 20172017-11-03
On Thu, 2 Nov 2017 20:50:28 -0700 (PDT), "nuny@bid.nes" <alien8752@gmail.com> wrote:>On Wednesday, November 1, 2017 at 9:42:22 PM UTC-7, 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. >> >> This is one of those recurring fads like fuel cells. > > Didn't someone post a link to a smartass who turned a VFD into an amplifier last time these things came up? > > > Mark L. FergersonVFDs have heated filament cathodes. Once upon a time, field-emission displays were the next big thing. https://en.wikipedia.org/wiki/Field-emission_display -- John Larkin Highland Technology, Inc lunatic fringe electronics
Reply by ●November 3, 20172017-11-03
On 2017-11-03, nuny@bid.nes <alien8752@gmail.com> wrote:> On Wednesday, November 1, 2017 at 9:42:22 PM UTC-7, 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. >> >> This is one of those recurring fads like fuel cells. > > Didn't someone post a link to a smartass who turned a VFD into an amplifier last time these things came up?commercial product: http://korgnutube.com/en/ -- This email has not been checked by half-arsed antivirus software
Reply by ●November 3, 20172017-11-03
On 11/02/2017 03:29 PM, DemonicTubes wrote:>> And we can't digitally emulate overdrive distortion of tubes? >> >> -- >> >> Rick C >> >> Viewed the eclipse at Wintercrest Farms, >> on the centerline of totality since 1998 > > It seems like we should be able to, in theory, however, if there is a solid state guitar amp that does this well I am unaware of it. I am open to suggestions, if anybody has any, as my life would be simpler if I didn't need to maintain and lug around tube amps. >There are probably like 500 different amps, effects pedals, rackmounts, and sequencer plug-ins that do that. Line 6 being probably the most well known company: <http://line6.com/>
Reply by ●November 3, 20172017-11-03
John Larkin <jjlarkin@highlandtechnology.com> 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.Atom probes use pulsed voltages around 2kV. What you are talking about is completely different from the IEEE article. https://en.wikipedia.org/wiki/Atom_probe>>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.Did you read the article? They use 10 volts and think they can reduce it to around 1-2 volts. They also can operate at atmospheric pressure using helium. The voltage is too low to ionize the gas, so there is no risk of damage from ion bombardment. See http://tinyurl.com/y9sjzl6a
Reply by ●November 3, 20172017-11-03
On a sunny day (Thu, 2 Nov 2017 15:21:30 -0700 (PDT)) it happened "nuny@bid.nes" <alien8752@gmail.com> wrote in <72700174-7df1-41b1-9aaf-2de469cecbec@googlegroups.com>:> It wasn't NASA that killed Project Orion. > >https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion) > > > Mark L. FergersonYes, Orion was a bit much actually, but NASA is just a part of US job creation, nothing to do with space. On top of that it is forbidden to find any sign of life outside earth for political and religious reasons, as NASA is basically a political organization with a large religious agenda controlling it. Remember Dr Levin's test for life on Mars was positive, I remember the announcement, http://gillevin.com/mars.htm CONTRADICTED hours later ... Dark voice, NO THAT EXPERIMENT IS WRONG Well if it was so wrong and you knew that in a few hours, then why send it up there? Just imagine earth would not be 4000 years old, and life was everywhere and not even Christian. I would have thought it would be a motivator for an other crusade :-) (by some Pieceful Pope) Anyways, they (politicians) ordered the Apollo designs destroyed, ordered an end to all nuclear propulsion experiments, invented the space shuttle as an endless around the block job creator (for their voters), and by now need a Russian taxi to get just a few hundred miles up.. I expect E Musk's Mars mission to also get head wind from this government, as No Extraterrestrial Life Shall Be Found. Mars from ESA in _true color_: http://sci.esa.int/mars-express/34508-reull-vallis/ Enlarged, without any color processing, try it yourself http://panteltje.com/panteltje/space/mars/lake2color.jpg From my website: http://panteltje.com/panteltje/space/mars/index.html In the mean time 'they' are coming with a huge 400 meter long spaceship to check us out: https://phys.org/news/2017-10-small-asteroid-comet-solar.html Well, could be a normal asteroid too of course... :-) Human beings, humming beans, apes, and what's the difference. From a logical perspective I think that China does not have that barrier against extraterrestrial life, and has the best chance for a Mars colony. They just move forward.
Reply by ●November 3, 20172017-11-03
On a sunny day (Fri, 03 Nov 2017 06:24:47 GMT) it happened Steve Wilson <no@spam.com> wrote in <XnsA822188C42BF8idtokenpost@69.16.179.22>:>Did you read the article? They use 10 volts and think they can reduce it to >around 1-2 volts. They also can operate at atmospheric pressure using >helium. The voltage is too low to ionize the gas, so there is no risk of >damage from ion bombardment.Well it is a prototype radiaton detector, look up GM tube. Last thing you want in space. And why 460 GHz? what is next? light? I have an UV LED flashlight to veryfy US dollars are false, how many GHz is that?>See
