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Pioneer Sa-9900 in the worst state i've ever seen an amp

Discussion in 'Pioneer Audio' started by reddish75, May 13, 2017.

  1. reddish75

    reddish75 Active Member

    Messages:
    189
    Here's the board pretty much finished, I tend to flit between projects so it's taken a while just to get this board finished. I ended up using the heatsinks that been bodged untill I find sutible ones as I needed an anchor point for the t0-126 transistors, it looks a little messy as I've had to point to point most of the traces around the pass transistors but it'll get the job done.

    [​IMG]2018-07-12_12-28-03 by chris reddish, on Flickr
    [​IMG]2018-07-12_12-28-21 by chris reddish, on Flickr
    [​IMG]2018-07-12_12-29-09 by chris reddish, on Flickr
    [​IMG]2018-07-12_12-28-40 by chris reddish, on Flickr
     
    slimecity and Hipocrates like this.

     

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  2. onwardjames

    onwardjames Hoardimus Maximus Subscriber

    Messages:
    15,873
    Location:
    Kentucky
    Great work, Reddish! Now put some pants on when you solder, lol!!

    Following with best wishes and great interest.

    @larryderouin - You allowed that Sansui to beat you?? Jeez, cannot imagine that level of damage.
     
    UncleBingo and Rsclj like this.
  3. reddish75

    reddish75 Active Member

    Messages:
    189
    I'm going to tackle the input board next and I'm looking to replace the Phono sockets while it's out, does anyone have a part number for ones that fit?
     
  4. Rsclj

    Rsclj Active Member

    Messages:
    438
    Location:
    Litchfield NH
    We seem to be running the same project in series...my board was bad...yours is way beyond bad...very nicely done
     
  5. restorer-john

    restorer-john Addicted Member

    Messages:
    6,513
    Location:
    Australia
    I like your taped precut tinned copper wire lengths for machine insertion. Where did you get them? I've always used reels of tinned copper.
     
  6. reddish75

    reddish75 Active Member

    Messages:
    189
    Last edited: Jul 17, 2018

     

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  7. reddish75

    reddish75 Active Member

    Messages:
    189
  8. Rsclj

    Rsclj Active Member

    Messages:
    438
    Location:
    Litchfield NH
  9. reddish75

    reddish75 Active Member

    Messages:
    189
    Trying to keep up on the restoration but time isn't my friend at the moment but I have managed to get the second psu board complete the Awr 0770, this one wasn't in terrible condition, just one damaged trace where the 10k pots had been replaced before, the wire wraps, however, are a completely different story.

    First job remove whats left of the wire wraps and label them, remove all components to be replaced then as nearly all the solder joints were dry completely unsolder every joint, clean everything replace components resolder and.......... a pretty damn good looking board again.

    [​IMG]2018-07-22_09-01-21 by chris reddish, on Flickr
    [​IMG]2018-07-22_09-01-41 by chris reddish, on Flickr
    [​IMG]2018-07-22_09-01-03 by chris reddish, on Flickr
    [​IMG]2018-07-22_09-00-48 by chris reddish, on Flickr
    [​IMG]2018-07-22_09-00-34 by chris reddish, on Flickr
    [​IMG]2018-07-22_09-00-09 by chris reddish, on Flickr
    [​IMG]2018-07-22_09-00-20 by chris reddish, on Flickr
     
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  10. onwardjames

    onwardjames Hoardimus Maximus Subscriber

    Messages:
    15,873
    Location:
    Kentucky
    That's beautiful work!!
     
  11. UncleBingo

    UncleBingo AK Subscriber Subscriber

    Messages:
    1,227
    Obviously a Tasmanian Devil...
     

     

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  12. Watthour

    Watthour Electron Rancher - JS3600

    I wasn't aware that a stick welder was an accepted method of connecting components to a foil trace on a board. Those "before" photos obviously prove otherwise.

    Seriously, though, I wonder is someone attempted to use low-lead alloy solder, not knowing the consequences.
     
  13. reddish75

    reddish75 Active Member

    Messages:
    189
    Time to make a start on the input board while I wait on parts, I managed to source a used input and tone control board to scavenge parts from mainly a new function switch shaft which on the 9900 is broken, the boards were from a SA-9500.

    The input board comes off In a complete module with very few wire removals (in this amp that doesn't overly matter) taking this off reveled the main part of the chassis is bent so added that to the list.

    With the module removed first job was to remove the switches from the donor pcb (I will add this is physically identical to the 9900 one but with layout differences that I couldn't be bothered to work into) when removed it would be completely pointless if I didn't clean them before installation, brasso is your friend here, see below pics,

    [​IMG]2018-07-25_01-07-42 by chris reddish, on Flickr
    [​IMG]2018-07-25_01-08-08 by chris reddish, on Flickr
    [​IMG]2018-07-25_01-08-33 by chris reddish, on Flickr
    [​IMG]2018-07-25_01-09-06 by chris reddish, on Flickr
    [​IMG]2018-07-25_01-09-32 by chris reddish, on Flickr
    [​IMG]2018-07-25_01-10-09 by chris reddish, on Flickr
    [​IMG]2018-07-25_01-10-31 by chris reddish, on Flickr
    [​IMG]2018-07-25_01-11-23 by chris reddish, on Flickr
    [​IMG]2018-07-25_01-11-43 by chris reddish, on Flickr
    [​IMG]2018-07-25_01-12-17 by chris reddish, on Flickr
     
    Hipocrates and Goldie99 like this.
  14. Goldie99

    Goldie99 Well-Known Member

    Messages:
    791
    Location:
    The original Boston, UK
    Excellent work on the switches !

    :lurk:
     
  15. reddish75

    reddish75 Active Member

    Messages:
    189
    Impedance selector pot (sealed) cleaned and lubricated, phono level pot cleaned and lubricated, easy access to clean this one.

    [​IMG]2018-07-25_08-02-01 by chris reddish, on Flickr
     
  16. Rsclj

    Rsclj Active Member

    Messages:
    438
    Location:
    Litchfield NH
    nice work!!:rockon:
     

     

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  17. Watthour

    Watthour Electron Rancher - JS3600

    That's nearly pornographic. Nice eye on the details.

    You mentioned early on that this amp was in the worst state you have ever seen. ALL of my receivers are that way, but then again, I live in Ill-Noise.
     
  18. Rsclj

    Rsclj Active Member

    Messages:
    438
    Location:
    Litchfield NH
    that Brasso tip was a godsend...thanks!
     
  19. Rsclj

    Rsclj Active Member

    Messages:
    438
    Location:
    Litchfield NH
    did you open the volume attenuator?
     
  20. Hipocrates

    Hipocrates Anti-Muppet Subscriber

    Messages:
    1,773
    Location:
    Costa Rica
    Inspiring work man!
     

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