Need suggestions for Filter Caps G-22000

Discussion in 'Exclusively Sansui' started by tder1, Apr 20, 2017.

  1. tder1

    tder1 New Member

    Messages:
    40
    Location:
    Mid Connecticut
    Hi All. It appears I will need to replace my Filter Caps. Previous problem turns bad so I need a new thread. Right side continuity straight thru Red and Blue. Everything else looks OK. Of course i'm back on Dim Bulb. Dont mind changing them anyway. Been looking for 2 days and can't find anything acceptable. Anybody have any source or Idea? Been scouring Mouser and DKey and everything is off size. Just to say i've had it all apart and checked all resistors. All good though I did lose 2 OP's. Should I go up on the uf also? Any suggestions are greatly appreciated.
    15000uf
    100V
    2.5 Diam 71mm
    4.2 long 106mm
     
  2. kevzep

    kevzep Its all about the Music

    Why do you think you need to replace the main filter caps?
     
  3. tder1

    tder1 New Member

    Messages:
    40
    Location:
    Mid Connecticut
    Hey Kev, Without getting too deep I had a slip on the right driver board that went all the back thru the amp and took out one of my mains fuses F102. All is reconnected and good except for the red and blue that come from the F Caps. there is a dead short cuz everytime I try to connect either to post 30 and 31 on 2903 I get spark, the DBulb goes bright and protection. Have good -/+ Voltage from D01 and D02. All Diodes good. Both leads which originate from the Caps have no resistance to ground. All resistors are good on the Caps and the Transistor Grid. All the T03"s are pulled. Whats on your mind?
     
  4. Hyperion

    Hyperion Roobarb & Custard Subscriber

    Messages:
    39,144
    Location:
    Hertfordshire, UK
    Holy smoke - you have a shorted filter capacitor? - the only measurement that would convince me is to disconnect everything from the filter capacitors and measure them with a meter. As this is quite an unusual, but a nonetheless possible fault, (and expensive to put right), this is what I would do before pronouncing them dead.
     
    Last edited: Apr 21, 2017
  5. tder1

    tder1 New Member

    Messages:
    40
    Location:
    Mid Connecticut
    Yes it is unusually possible and that's what my symptoms are no doubt. I will take your statement as good advice. All the Factory Work under there is quite stout and looks like you need a blowtorrch to release the solder ;-). Never the less I will be doing a disassembly today and test them butt naked. I also see no other sure way to confirm it. Thanks for the chime in, Will advise.
     
    Hyperion likes this.
  6. kevzep

    kevzep Its all about the Music

    I find it very difficult to believe you have shorted out one of those caps.....

    Do what John says and pull the terminals, measure it on its own without being connected to anything...
     
    Hyperion likes this.
  7. kevzep

    kevzep Its all about the Music

    I got some nice 22,000µf caps....weren't difficult to find....I got them locally in NZ, so must be able to get them over there in the USA...
     
  8. Overundr1

    Overundr1 AK Subscriber Subscriber

    Messages:
    2,267
    Location:
    Mississippi
    Ditto, if you have fully discharged filter caps a dbt will glow bright for a short period as they charge back up again. As I recall it takes 5 seconds or more for a similar unit (Pioneer sx-1980) to dim down after cycling the main caps. Also, if you had a cap of that value discharge (short) to ground while charged the bang would have scared you out of the room, its not pretty when it does happen. Be careful working around caps that big, they can carry a lethal shock hazard. Finally, if you decide to pull and test them make yourself a discharge tool and be sure to run them down to 0 potential before attempting to remove them. I have a 100w lightbulb with soldered leads to mini-grabbers for that process.
     
  9. JOMARK911

    JOMARK911 Super Member

    Messages:
    2,474
    Location:
    Athens Greece

    Yeah me too , it's rather difficult to have those shorted.
    But then again if you say they are shorted then of you go.
     
  10. tder1

    tder1 New Member

    Messages:
    40
    Location:
    Mid Connecticut
    OK, took it all down and the right rear was shorted though I did have a self induced short right back to F01. Can't reason it out except we have 40 year old stuff here and Caps do have a finite life. All the better, Here's what I ended up with. Back where I started with missing Bias voltage.Thanks Guys

    nichi.JPG nichi.JPG
     
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