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  • Article from 2012 - "nano" vacuum tube

    From Big Bad Bob@21:1/5 to All on Tue Feb 9 10:55:00 2021
    https://www.sciencemag.org/news/2012/05/return-vacuum-tube

    <quote>
    The new device is a cross between today's transistors and the vacuum
    tubes of yesteryear. It's small and easily manufactured, but also fast
    and radiation-proof. Meyyappan, who co-developed the "nano vacuum tube,"
    says it is created by etching a tiny cavity in phosphorous-doped
    silicon. The cavity is bordered by three electrodes: a source, a gate,
    and a drain. The source and drain are separated by just 150 nanometers,
    while the gate sits on top. Electrons are emitted from the source thanks
    to a voltage applied across it and the drain, while the gate controls
    the electron flow across the cavity. In their paper published online
    today in Applied Physics Letters, Meyyappan and colleagues estimate that
    their nano vacuum tube operates at frequencies up to 0.46 terahertz—some
    10 times faster than the best silicon transistors.
    </quote>

    cool stuff. Seems to work without a heated cathode. not sure if voltage "across the source and the drain" is in any way responsible for
    thermionic emission or some other mechanism...


    --
    (aka 'Bombastic Bob' in case you wondered)

    'Feeling with my fingers, and thinking with my brain' - me

    'your story is so touching, but it sounds just like a lie'
    "Straighten up and fly right"

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pallison49@gmail.com@21:1/5 to Big Bad Boob on Tue Feb 9 15:32:36 2021
    Big Bad Boob wrote:
    ---------------------------------
    https://www.sciencemag.org/news/2012/05/return-vacuum-tube

    cool stuff. Seems to work without a heated cathode. not sure if voltage
    "across the source and the drain" is in any way responsible for
    thermionic emission or some other mechanism...


    ** Lemme see - there is no vacuum, no tube, no thermionic emission and
    electrons travel across a tiny air space. Right ?

    " VaccumTube" my arse.

    The author must be a u-tuber - deliberately *misnaming* to get clicks.

    ..... Phil

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Lord Valve@21:1/5 to palli...@gmail.com on Tue Feb 9 16:41:35 2021
    On Tuesday, February 9, 2021 at 4:32:37 PM UTC-7, palli...@gmail.com wrote:
    Big Bad Boob wrote:
    ---------------------------------
    https://www.sciencemag.org/news/2012/05/return-vacuum-tube

    cool stuff. Seems to work without a heated cathode. not sure if voltage "across the source and the drain" is in any way responsible for
    thermionic emission or some other mechanism...

    ** Lemme see - there is no vacuum, no tube, no thermionic emission and electrons travel across a tiny air space. Right ?

    " VaccumTube" my arse.

    The author must be a u-tuber - deliberately *misnaming* to get clicks.

    ..... Phil

    It actually *is* a vacuum tube, but it's pretty flaky. There are a bunch
    of effects pedals out now (and an amp or two) which use it. Here's
    a couple of URLs on it, one from the manufacturer:

    https://korgnutube.com/en/

    https://diyaudiostore.com/products/korg-nutube

    The second one has some numbers and graphs and stuff.
    If you want to mess with one, they'll be glad to sell it to you
    for only fifty bucks US. (OUCH!)

    Lastly, you should watch this - this guy is so absolutely clueless
    you'll be ROFL by the time you get to the end. His comment about
    the exhaust port is especially hilarious:

    https://www.youtube.com/watch?v=6Azl1vzoLpA

    He probably posts to alt.guitar.amps. ;-)

    Lord Valve

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pallison49@gmail.com@21:1/5 to Lord Valve on Tue Feb 9 18:22:18 2021
    Lord Valve wrote:
    ==================
    palli...@gmail.com wrote:

    It actually *is* a vacuum tube, but it's pretty flaky.

    ** Fraid you are barking up the wrong tree.

    The "science mag"' article is about a totally different development.
    ================================================

    Lastly, you should watch this - this guy is so absolutely clueless
    you'll be ROFL by the time you get to the end. His comment about
    the exhaust port is especially hilarious:

    https://www.youtube.com/watch?v=6Azl1vzoLpA

    He probably posts to alt.guitar.amps. ;-)


    ** The " guitologist " is a hoot.

    Reminds me of the Middle Ages when barbers carried out surgery on people cos they owned the sharpest knives.


    ..... Phil

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Lord Valve@21:1/5 to palli...@gmail.com on Thu Feb 11 15:05:57 2021
    On Tuesday, February 9, 2021 at 7:22:19 PM UTC-7, palli...@gmail.com wrote:
    Lord Valve wrote:
    ==================
    palli...@gmail.com wrote:

    It actually *is* a vacuum tube, but it's pretty flaky.
    ** Fraid you are barking up the wrong tree.

    The "science mag"' article is about a totally different development. ================================================

    I shoulda took a closer look - sorry.


    Lastly, you should watch this - this guy is so absolutely clueless
    you'll be ROFL by the time you get to the end. His comment about
    the exhaust port is especially hilarious:

    https://www.youtube.com/watch?v=6Azl1vzoLpA

    He probably posts to alt.guitar.amps. ;-)

    ** The " guitologist " is a hoot.

    Reminds me of the Middle Ages when barbers carried out surgery on people cos they owned the sharpest knives.


    ..... Phil

    The authorities in Oz give you a covid shot yet? I'm on
    the list - supposed to be priority, I'm 73 - but I ain't seen
    jack shit so far.

    LV

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pallison49@gmail.com@21:1/5 to Lord Valve on Thu Feb 11 15:46:09 2021
    Lord Valve wrote:
    ================

    ** The " guitologist " is a hoot.

    Reminds me of the Middle Ages when barbers carried out surgery on people cos they owned the sharpest knives.

    The authorities in Oz give you a covid shot yet? I'm on
    the list - supposed to be priority, I'm 73 - but I ain't seen
    jack shit so far.


    ** Later this year maybe, priority folk like emergency service workers will get first go in March.

    The risk here in NSW is very low.


    ..... Phil

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Big Bad Bob@21:1/5 to Lord Valve on Fri Feb 12 10:35:07 2021
    On 2021-02-09 16:41, Lord Valve wrote:
    It actually *is* a vacuum tube, but it's pretty flaky. There are a bunch
    of effects pedals out now (and an amp or two) which use it. Here's
    a couple of URLs on it, one from the manufacturer:

    https://korgnutube.com/en/

    they would e-mail the data sheet to me but I have to give them sales
    contact info first. Naaah. I'll wait until digikey has them.

    https://diyaudiostore.com/products/korg-nutube

    The second one has some numbers and graphs and stuff.
    If you want to mess with one, they'll be glad to sell it to you
    for only fifty bucks US. (OUCH!)

    if I wanted to build an amp to test a design it's probably worth it.

    Looking at the curves, it runs with a positive grid voltage in most of
    the examples. that's not entirely ideal [obviously] especially when
    plate current is measuree in microamps.

    apparently the ref circuit solves that by using a JFET front-end as a
    voltage follower.

    Still interesting, but I can't see any advantages of this over using a
    MOSFET other than to say "it is a tube". HOWEVER... I would definitely
    expect the technology to improve and at some point use an indirectly
    heated cathode.

    Having a mu factor of 14 isn't all that exciting either. I'd expect 50
    or 60 to be of real use (like a 12AT7) in a preamp, or 100 like a 12AX7.

    still - the low volts, low heater power, and small physical size
    definitely have an appeal.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)