Hurt my AU-717 (current went wrong way, channel dead )

Discussion in 'Exclusively Sansui' started by delboyko, Dec 28, 2017.

  1. delboyko

    delboyko New Member

    Messages:
    13
    Well, I ran a quick check and here are the results.

    Nonworking driver: C01 (capacitance: unmeasurable; Resistance 0,5 ohm)
    Working driver: C01 (Capacitance: 160 pf; Resistance: unmeasurable)

    Everything measured on PCB.
     
  2. petehall347

    petehall347 the brandy coffee man

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    Location:
    uk.. the middle bit
    you need to remove it and test again .
     
  3. Bigdrive

    Bigdrive Member

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    75
    Location:
    Kelowna
    Mine in circuit using two different dmm c01 resistance 57k, capacitance unmeasurable. My equipment will not read cap in circuit.
     
  4. Bigdrive

    Bigdrive Member

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    75
    Location:
    Kelowna
    Caution, if you remove that cap, put a heat sink on the leads or you will cook it!
     
  5. petehall347

    petehall347 the brandy coffee man

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    Location:
    uk.. the middle bit
    think its already cooked by the looks of things
     
  6. petehall347

    petehall347 the brandy coffee man

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    is it a styrene cap ?
     
  7. Bigdrive

    Bigdrive Member

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    75
    Location:
    Kelowna
  8. petehall347

    petehall347 the brandy coffee man

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    Location:
    uk.. the middle bit
    only ever seen one of those short .was signal path in a valve guitar amp . this night be the second one i have known about . if you dont want to remove it lift one end of R02 and test again . this leaves the cap and the fet . but resistances dont add up if fet shorted
     
  9. delboyko

    delboyko New Member

    Messages:
    13
    Removed the R02 leg and measured again:

    C01 Capacitance: unmeasurable; Resistance 0,5 ohm. Hope it's the only thing wrong.
    Should I go with a PP or C0G cap?
     
    Last edited: Jan 13, 2018 at 9:38 AM
  10. Hyperion

    Hyperion Roobarb & Custard Subscriber

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    Last edited: Jan 13, 2018 at 9:49 AM
  11. delboyko

    delboyko New Member

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    Croatia (EU). Mouser was choice but smallest they have is 150pF
     
  12. Hyperion

    Hyperion Roobarb & Custard Subscriber

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  13. delboyko

    delboyko New Member

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    I'll search around, although I doubt it.

    Still have to find the culprit on power supply board.
     

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