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D&A transformer

Discussion in 'Home Brew' started by intercepter, Jan 26, 2010.

  1. intercepter

    intercepter Member

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    i have a old D&A Maverick 4 driving 4,just wondering what voltage is on the transformers.how close are they to what i need to build a amp with 811a tubes in it.the D&A isn't working to test the voltage.thanks


     
    #1 intercepter, Jan 26, 2010
    Last edited: Jan 26, 2010

  2. Shockwave

    Shockwave Sr. Member

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    The D&A used 660 volt AC transformers. If you used a voltage doubler it would provide about 1800 volts DC under no load. That's in the ballpark for an 811A. You'll probably need more then one transformer if you use more then 2 tubes because of current limitations.
     
  3. intercepter

    intercepter Member

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    i have 2 transformers out of the D&A,was thinking about using 4 811a tubes.this should make a good little amp.don't know if i can use anymore of the parts from the D&A.thanks
     
  4. JoeDirt

    JoeDirt Well-Known Member

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    2 D&A transformers will run 4 811's just fine! I hammered my 811 box on D&A's for a long time, I finally toasted a transformer when I installed some 572b's :oops:
     
  5. intercepter

    intercepter Member

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    can i use any other parts out of the D&A,i also need a case,the case i have is to small for the 811a's.any places to order large cases.thanks
     
  6. JoeDirt

    JoeDirt Well-Known Member

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    I dont know much about the D&A's, you might be able to use the variable air gap caps?
     
  7. Radio Tech

    Radio Tech Radio Operator

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    I do not think there will be enough capacitance to load it down. D&A used some tight capacitors and less voltage.
     
  8. HiDef

    HiDef Active Member

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    The load cap might be OK but the tune cap will probably arc.

    Put the 811s in there sideways like a 30L-1 Collins. They work just fine like that.
     
  9. intercepter

    intercepter Member

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    i have another case its bigger but i will have to lay the 811'S on the side.ill look for another tune cap.thanks.
     
  10. JoeDirt

    JoeDirt Well-Known Member

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    811 work better vertical, if your going to run it hard! They plates like to sag and short out!

    If your going to run it in specs then you will be fine!
     

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