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Discussion in 'Exclusively Sansui' started by Willy6, Aug 17, 2017.

  1. Willy6

    Willy6 AK Subscriber Subscriber

    Messages:
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    Location:
    Pacific northwest
    The 500 ohm Trimmers worked on F-2835 (I was able to adjust within specs but only after a voltage drop everytime I check it)but after I put those in F-2833s voltages are all over the place and it went into protection..
     
  2. Hyperion

    Hyperion Roobarb & Custard Subscriber

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    Location:
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    The F-2835 offset voltage will wander all over the place +/- 100mV or more - it is normal, it doesn't affect sound quality and unless wildly out is not enough to trigger protection.

    Regarding F-2833 - check you have the +/- 10V adjusted correctly.
     
    Last edited: Oct 6, 2017
  3. Willy6

    Willy6 AK Subscriber Subscriber

    Messages:
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    Location:
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    there is either some bad resistors or bad jfets on f-2833 voltages are all over the place..
     
  4. Hyperion

    Hyperion Roobarb & Custard Subscriber

    Messages:
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    Location:
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    Lets hope it isn't any of the JFET's :( - check the +/- 10V regulators - and then do a wiring check (did you completely disconnect the board?), and double check other work done on the board if any. ;)
     
  5. Willy6

    Willy6 AK Subscriber Subscriber

    Messages:
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    Location:
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    Protection problem solved..I found a bad resistor and a couple of bad solder joints on the protection board F-2840 and on the rectifier board F-2928.. 20171009_174108.jpg 20171009_174229.jpg
     
    Hyperion likes this.
  6. Willy6

    Willy6 AK Subscriber Subscriber

    Messages:
    1,023
    Location:
    Pacific northwest
    I still have a slight problem with my left channel though..On F-2833 I'm getting a perfect -/+ 10v on the right and a bad -/+ 35mv on the left side..
     

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