Results 1 to 10 of 31

Thread: 3-Knob Tube Driver Build.

Hybrid View

Previous Post Previous Post   Next Post Next Post
  1. #1
    Quote Originally Posted by Marcel View Post
    Simplest explanation for multiplier circuits is it's a bit like voltage stacking.
    We all know how with a diode and a cap we can convert AC into DC, well, if we do it multiple times in (theoretical) parallel and then put all the resultant DC voltages in series you can achieve higher DC voltages from lower AC voltages.

    The mathematics and the trickery pokery of reality are a lot more complex but that only really concerns the designers... for us we just need to be able to recognise the basic circuit and to know what voltage we can expect at the output... Usually you can recognise it as an AC power signal of some sort going to a bunch of diodes (often 3 or more) in series with appropriately voltage'd caps (usually tied to chassis/earth) connected between every diode with a higher voltage needing 'load' at the end.

    One thing to remember is only voltage is multiplied...Power remains the same.... Discounting any losses in the circuit If we have 12v at 1A at the input to the multiplier then if we multiply up to 24V we can only consume 0.5A, and at 48V we will have 0.25A at our disposal, and if we multiply up to 96V then the maximum theoretical current we can draw is only 0.125A (12V x 1A = 96V x 0.125A = 12W assuming nil losses). In reality due to losses and the effects of 'loading' the multiplier to 96V will probably only supply a maximum of about 0.1A before drastically dropping of in the higher voltage it can supply.
    Ok, that makes some sense to me. I still have to think about it a bit I think...
    #001 (LP-1S) [finished - co-runner up Nov 2018 GOTM]
    #002 (WL-1)
    #003 (MPL Megacaster - semi scratch build) [finished]
    #004 (ST-1 JR - Arachnoid Superhero build) [finished]
    #005 (LP jr)
    #006 (TL-1A)

    Junk shop acoustic refurbs (various)
    'The TGS Special'

  2. #2
    GAStronomist DrNomis_44's Avatar
    Join Date
    Dec 2014
    Location
    Darwin,NT Australia
    Posts
    5,552
    Quote Originally Posted by JohnH View Post
    Ok, that makes some sense to me. I still have to think about it a bit I think...

    No worries, take your time cause it is a bit hard to understand at first, I went through the same learning-process when I first started out in electronics.

  3. #3
    Quote Originally Posted by DrNomis_44 View Post
    No worries, take your time cause it is a bit hard to understand at first, I went through the same learning-process when I first started out in electronics.
    Yeah, it's pretty mind bending. My brother summed up my feelings perfectly at a gig a few months back - we were both pretty drunk and standing at the side of the stage and apropos of nothing he just kind of shrugged, shook his head and exclaimed 'but what even IS electro-magnetism?!?'
    #001 (LP-1S) [finished - co-runner up Nov 2018 GOTM]
    #002 (WL-1)
    #003 (MPL Megacaster - semi scratch build) [finished]
    #004 (ST-1 JR - Arachnoid Superhero build) [finished]
    #005 (LP jr)
    #006 (TL-1A)

    Junk shop acoustic refurbs (various)
    'The TGS Special'

  4. #4
    GAStronomist DrNomis_44's Avatar
    Join Date
    Dec 2014
    Location
    Darwin,NT Australia
    Posts
    5,552
    Quote Originally Posted by JohnH View Post
    Yeah, it's pretty mind bending. My brother summed up my feelings perfectly at a gig a few months back - we were both pretty drunk and standing at the side of the stage and apropos of nothing he just kind of shrugged, shook his head and exclaimed 'but what even IS electro-magnetism?!?'

    Scientists have theorized about what Electro-Magnetism is, but personally I think we are barely scratching the surface with our current understanding.

  5. #5
    GAStronomist Simon Barden's Avatar
    Join Date
    Oct 2016
    Location
    Reading, UK
    Posts
    10,547
    Quote Originally Posted by DrNomis_44 View Post
    Scientists have theorized about what Electro-Magnetism is, but personally I think we are barely scratching the surface with our current understanding.
    Very good, Doc.

    Don't forget that as you increase the voltage, it becomes more dangerous to mess about with. You need to be sure that all your wires and components are suitably rated for that voltage. Each component in the multiplier might not have a large voltage across it, but the voltage with respect to ground is increasing with each step.

  6. #6
    GAStronomist DrNomis_44's Avatar
    Join Date
    Dec 2014
    Location
    Darwin,NT Australia
    Posts
    5,552
    Quote Originally Posted by Simon Barden View Post
    Very good, Doc.

    Don't forget that as you increase the voltage, it becomes more dangerous to mess about with. You need to be sure that all your wires and components are suitably rated for that voltage. Each component in the multiplier might not have a large voltage across it, but the voltage with respect to ground is increasing with each step.

    Good point, and you're right about that...pun not necessarily intended but it did work out pretty well in the end I must say.
    Last edited by DrNomis_44; 26-01-2018 at 05:34 PM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •