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diyAudio group buy Paradise R3 phono stage boards

Discussion in 'd.i.y.' started by Markus S, Aug 9, 2012.

  1. sq225917

    sq225917 situation engineer


    Chilly pm ynwoan for panels.
     
  2. Avinunca

    Avinunca Apprentice Grumpy Pensioner

    Thanks guys. I will get some appropriate resistors.
     
  3. 337alant

    337alant Negatively Biased

    Si
    Do you know if it makes any difference as I did my Power supply with CRCLC not CLCRC ?.

    Alan
     
  4. sq225917

    sq225917 situation engineer

    I've never measured it but it's nearly always done that way.
     
  5. sq225917

    sq225917 situation engineer

    Try the 20 watt Caddock t220 package parts, easy to heatsink
     
  6. slawekt

    slawekt pfm Member

    Simulate it in PSU Designer software
     
  7. Avinunca

    Avinunca Apprentice Grumpy Pensioner


    Just checked my voltages so that I can order some new dropper resistors. The +V are both +26.7V which I assume is fine. The -V however are both -32V. Is it normal to have less current demand on the negative rails?
     
  8. sq225917

    sq225917 situation engineer

    Nope. If you are running Calvin's, disconnect them and measure the rails before the shunt reg. If voltages become even your Calvin's are bad, if they don't your shunt reg is bad.

    Watch how long it takes the led strings to light up on the sides of the boards, they should come up together, within half a second of each other.

    Of course you could have a short elsewhere on the board.
     
  9. Avinunca

    Avinunca Apprentice Grumpy Pensioner

    It's odd that I have the same conditions on both boards. Shunt op voltages are ok. I bought these amp/psu boards completed. What is the normal current consumption (inc Calvin boards)? I'm wondering which are correct - the + rails or the -rails. Will try to discon the Calvins.
     
  10. Avinunca

    Avinunca Apprentice Grumpy Pensioner

    Quick check of currents before disconnecting - negative supplies 174ma and positive supplies 218ma. Positive rail leds illuminate fractionally faster. Shunt outputs are around 18.5V
     
  11. sq225917

    sq225917 situation engineer

    Are you using Calvins output boards?
     
  12. Avinunca

    Avinunca Apprentice Grumpy Pensioner

  13. sq225917

    sq225917 situation engineer

    How did yoy zero them?
     
  14. Avinunca

    Avinunca Apprentice Grumpy Pensioner

    Although I have a set of boards to build, this phono amp I bought completed - or so I thought. I built the pre-regs. I've PM'd the seller querying the mismatch.
     
  15. sq225917

    sq225917 situation engineer

    Matching all the parts and doing all the set on test stuff is where the magic lies.

    Disconnect signal in out from the Calvins.
    Fit a 100K resistor into the empty slot.
    Adjust shunt trimpot to get equal voltage then adjust Calvin trim pot until voltages match and yhe led strings light up equally.
    This takes a few go rounds.
    Then remove the 100K and reattach signal wires and it'll be golden.

    I imagine there's a lot of part dialled in Paradises out there.
     
  16. chiily

    chiily PFM Special Builder

    Si,

    When you say, ",,,then adjust Calvin trim pot until voltages match..", where on the Calvin's are you measuring the voltage(s)?

    Ta
     
  17. sq225917

    sq225917 situation engineer

    Across the Top left and second resistors down on the right. Think it's the 22r, I'd have to check the schematic.
     
  18. sq225917

    sq225917 situation engineer

    I'll open mine tomorrow and check
     
  19. Avinunca

    Avinunca Apprentice Grumpy Pensioner

    Simon, I have prepared one of my Calvin boards for adjustment .
     
  20. sq225917

    sq225917 situation engineer

    I get 93mv and 93.5mv across those two resistors, r6and r11, the 2.2ohm parts.. Each time you redial the calvin board you'll need to adjust the trim pots on the main board. Eventually it should all even out.
     

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