Thermionic diodes

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  • capwizard
    Badcaps Legend
    • Jun 2016
    • 1991
    • USA

    #1

    Thermionic diodes

    Thermionic diodes valve diodes Selenium rectifier

    Today they are still used in a few high power applications where their ability to withstand transient voltages and their robustness gives them an advantage over semiconductor devices. The recent (2012) resurgence of interest among audiophiles and recording studios in old valve audio gear such as guitar amplifiers and home audio systems has provided a market for the legacy consumer diode valves.

    http://www.schoolphysics.co.uk/age14...ode/index.html

    As you may know, if a metal is heated it may emit electrons. The hotter it is the more electrons are emitted. Of course some materials are better than others for emitting electrons. This emission of electrons due to the heating of a surface is called thermionic emission. This is the basis of the thermionic diode.

    http://www.schoolphysics.co.uk/age16...ode/index.html

    This is basically a two-electrode valve [an anode and a heated cathode] the space between the anode and cathode being evacuated.
    Attached Files
    Last edited by capwizard; 02-18-2017, 09:56 AM.
  • capwizard
    Badcaps Legend
    • Jun 2016
    • 1991
    • USA

    #2
    Re: Thermionic diodes

    Homemade Vacuum Tube Diode.
    http://www.sparkbangbuzz.com/els/hm-vac-diode-el.htm


    making a fleming diode vacuum tube 1
    https://www.youtube.com/watch?v=IUPizgcWimw

    making a fleming diode vacuum tube 2
    https://www.youtube.com/watch?v=5l5gxuUCof0

    making a fleming diode vacuum tube 3
    https://www.youtube.com/watch?v=W6PR52OChM0

    https://www.youtube.com/watch?v=lnZt00IY88Y

    https://www.youtube.com/watch?v=iVr68eT7kfM

    https://www.youtube.com/watch?v=sIj1Yy1kMG8

    https://www.youtube.com/watch?v=xw3uXIiRQ60
    Attached Files
    Last edited by capwizard; 02-18-2017, 10:07 AM.

    Comment

    • PeteS in CA
      Badcaps Legend
      • Aug 2005
      • 3579
      • USA, Unsure of Planet

      #3
      Re: Thermionic diodes

      The 5U4GB is a classic vacuum tube rectifier.
      PeteS in CA

      Power Supplies should be boring: No loud noises, no bright flashes, and no bad smells.
      ****************************
      To kill personal responsibility, initiative or success, punish it by taxing it. To encourage irresponsibility, improvidence, dependence and failure, reward it by subsidizing it.
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