using oscilloscope crt+power supply

Discussion in 'The Projects Forum' started by uv147, Jan 29, 2016.

  1. uv147

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    Dec 24, 2015
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  2. Hypatia's Protege

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    Display of even a 'dot' will require correct biasing (i.e. cathode, focus, pre-acceleration, etc...) -AND- charging of the deflection plates such that the beam impinges upon the 'screen area' (It appears that the first PSU (linked above) provides filament power and final/post accelerator potential) --- What are you trying to do?

    Best regards
    HP:)
     
    Last edited: Jan 29, 2016
  3. uv147

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    Dec 24, 2015
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    i am trying to deflect the beam using my own helmholtz coils
    i am trying to deflect the beam using my own helmholtz coils
     
  4. Dodgydave

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    Jun 22, 2012
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    The psu wont have any line scan circuits or vertical amplifier, it should just put the beam in the centre position with focus and brightness adjustment,

    As for deflection, the tube uses deflection plates inside to move the beam up down, left right, not coils.

    i would contact the seller and ask them for confirmation.
     
  5. uv147

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    well i tried, they said they think it's possible but never tried it
     
  6. Hypatia's Protege

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    It is very unlikely that the beam will be directed 'dead center' (or even on-screen) with the deflection plates merely floating or bonded/tied --- In my experience significant 'inherent' offset is always present...

    Of course magnetic deflection of any CRT is possible - so long as you can manage location of the coils despite 'bulb' geometry, shielding, any 'neck pins', etc...:)

    Best regards
    HP
     
    Last edited: Jan 29, 2016
  7. uv147

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    Dec 24, 2015
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    so can i make the crt shoot a beam without the scope iself? because i see there is a wire in there not connected to the power suply in the picures
    thank you
     
  8. Hypatia's Protege

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    @uv147

    Not to kibitz, however I'm bound to say that magnetic deflection is a waste of 'high speed' CRTs --- What is your intended application?
     
  9. bertus

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  10. uv147

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    physics competition in school
     
  11. Hypatia's Protege

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    You seem to be under some misapprehension -- You are, in point of fact, contemplating construction of an oscilloscope!:confused:

    Best regards
    HP
     
  12. Hypatia's Protege

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    Fair enough! -- Although I'm here to tell you that magnetic deflection of those tubes is as using a Lamborghini to deliver beer!:eek: --- You'll find it less expensive and much easier to use a TV CRT for your purposes!:cool:

    Best regards
    HP:)
     
  13. Dodgydave

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    Do you want to make an Oscilloscope or just want to make the beam move left, right,up,down???
     
  14. bertus

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    Hello,

    Here is the schematic of the 2445 HV powersupply and the CRT:

    2445_HV_powersupply.png

    Bertus
     
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  15. uv147

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    Dec 24, 2015
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    yes kind of...

    i only need the beam to move right up left and down, i am controling the beam by changing the current in the coils

    i tried it, but it turns out to be almost impossible to disconnect the deflection plates, and using a color crt is too

    thank you bertus, but the question is will the power suply and the crt will be enough for my needs or will i need to buy a full oscilloscope in order to make the crt just shoot a beam?
     
  16. Dodgydave

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    Are you making an oscilloscope using a colour tv crt tube,???
     
    Last edited: Jan 29, 2016
  17. bertus

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    Hello,

    A CRT as shown uses voltage on the deflection plates to move the beam.

    In the posted schematic, you will see some controls like focus, astig and trace rotaion.
    Those are NOT on the supply.

    Bertus
     
  18. Hypatia's Protege

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    TV CRTs are magnetically deflected (hence no deflection plates) --- If you mean that the deflection yoke is chemically bonded to the neck/bulb, please be advised that it may readily be removed via application of ketone solvents (e.g. acetone) --- Also, although a colour tube will suffice, a monochrome CRT would be better applied to your demonstration... :)

    Best regards
    HP
     
  19. uv147

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    Dec 24, 2015
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    as i said above, the deflection plates are not needed as part of my demonstration, as i plan to move the beam using helmholtz coils
     
  20. Hypatia's Protege

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    That's my point -- Just remove the yoke (using solvent) - then replace it with your coil{s}:)

    Again, television CRTs contain no deflection plates! --- So... no worries about 'interference' from same:cool::cool::cool:

    Best regards
    HP
     
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