Help powering a 450v dekatron?

Discussion in 'The Projects Forum' started by Bp_968, Mar 14, 2014.

  1. Bp_968

    Thread Starter New Member

    Dec 25, 2013
    21
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    I'd like to build a step up PS to power my dekatron tubes I have laying around. One of the models will require 450v and the other will require 600v!

    It looks like I'll need 180mw minimum to power the og4, not sure on the og8.

    I have a few mc34063 ICs which are supposed to work well for this.

    I found this calculator but I'll be honest I'm not sure what some of the values are for (ripple for example)

    http://dics.voicecontrol.ro/tutorials/mc34063/


    Another option is I have a 13v AC power brick (yes, it outputs AC) with a 4A max current rating. Could I build a voltage multiplier on the end of that?

    Data sheets and info on the dekatrons.

    Og-4 and og-8 dekatrons.

    http://www.tube-tester.com/sites/nixie/datdekat/OG4/og4.htm

    http://www.decadecounter.com/vta/articleview.php?item=287

    http://www.decadecounter.com/vta/articleview.php?item=276

    Thanks for any help!!

    Ben
     
  2. richard.cs

    Member

    Mar 3, 2012
    162
    31
    How about a 12V:240V transformer on the output of your ac power brick driving a doubler or a trippler?
     
  3. Bp_968

    Thread Starter New Member

    Dec 25, 2013
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    Any suggestions on where to get a transformer? Ebay seems kind of hit or miss on them.

    Another idea I had was to gut a cheap 5$ car inverter and using a double/tripler on that. Regardless which method is used I do believe I need it to be DC voltage when it goes to the dekatron, which is why I was hoping to just make one using a MC34063. I'll watch eevblogs video on the subject here in a minute. :)
     
  4. richard.cs

    Member

    Mar 3, 2012
    162
    31
    Take a look on ebay UK (or any other 240V country). This one would do the job and ships worldwide:
    http://www.ebay.co.uk/itm/MYRRA-442...al_Components_Supplies_ET&hash=item5af33d76e8

    Getting reasonable d.c. out of a multiplier isn't too hard, it's just a question of having enough capacitance. If you'd like a fairly stable output you can also shunt-regulate with a string of high voltage zeners.

    For simplicity and reliability I'd lean towards the low frequency transformer-multiplier supply. The transformer above, 12 diodes, 6 capacitors gets you your 600V.
     
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  5. Bernard

    AAC Fanatic!

    Aug 7, 2008
    4,176
    397
    If you will pay the postage, I'll look in my junk box for a 120 V, 60 Hz, plate, filament transformer; no charge for transformer, if I have proper one.
     
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  6. Bp_968

    Thread Starter New Member

    Dec 25, 2013
    21
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    that would be awesome! By 120v60hz your talking about a transformer going from line voltage to 450-600V?

    thanks for the suggestions and help everyone, its so much fun learning all this stuff (and a tad overwhelming.. Ive been trying to figure out FPGAs recently as well...)

    bp
     
  7. Bernard

    AAC Fanatic!

    Aug 7, 2008
    4,176
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    Shucks!!, turns out they are either chokes, filament x-formers, or non discript multilead with no identifiable 120 line; where did the 5V, 6.3V & 300-0-300V one go? Maybe when I find my missing marbles, other missing items will turn up.
     
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  8. Threeneurons

    New Member

    Jul 12, 2016
    19
    10
    Dekatrons are cold cathode gas filled counter tubes. Common ones like the Russian OG-4, British GC10B, and Sylvania 6802 are neon filled, and require a minimum supply voltage ~380V. Their current draw is quite low. Nominally ~350uA. That means you don't need a large amount of power. Multiplier ladders are okay to use here. Like a neon bulb, or nixie, the current needs to be limited. Voltage is relatively arbitrary, as long as it exceeds the minimum strike value. Once the dekatron strikes, the voltage from anode, to lowest cathode, is ~200V, for neon types.

    Here is a drawing for a nixie supply, that can deliver upto ~190V. The limit is the FET used, since its max Vds is 200V.
    [​IMG]
    These are sold as kits, but feel free to use this circuit. Its mine & have all rights to it. It can be altered to output higher voltage, but not straight to 450V. From past experience, I've found boosting straight to 450V puts a lot of strain on components. Boosting to ~350V is about as high as I'll go, with a single stage. Its better to boost to ~230V, then use a multiplier stage, to get to ~450V. Or use this circuit, and add two multiplier stages to triple the voltage, as shown below:
    [​IMG]
    The above, circuits, use the MC34063. You can use other circuits. Below is one that uses an old LM393 dual voltage comparator:
    [​IMG]
    Again, all drawings are mine.
     
  9. 430things

    New Member

    Sep 14, 2016
    1
    0
    @Threeneturons, location of C1 in your NK01 is affecting efficiency and causing inductor noise. C1 should be located before current sensing resistors.
     
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