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The restoration of a Yamaha CA-2000 (Japanese CA-2010)

Discussion in 'Yamaha' started by Mr. Yamaha, Oct 4, 2017.

  1. avionic

    avionic " Black Knights " Subscriber

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    I like to use Nichicon " EP " in the protect circuit. 105° close to those pass transistors.

    ES's ( 85°) I use in the signal path.

    Your look'n good MrYamaha. Great photos as well.
     
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  2. Mr. Yamaha

    Mr. Yamaha Not so much Yamaha lately...

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    Thanks Dave! Didn't know about the EP's existence. Will consider them for the next time, thanks for the tip :thumbsup:
     
  3. avionic

    avionic " Black Knights " Subscriber

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    Those bi - polar caps on the power suppy board are for the DC detection circuitry in the protect circuit.
     
  4. Mr. Yamaha

    Mr. Yamaha Not so much Yamaha lately...

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    So no need for the Muse series I guess :rolleyes: I thought the ES's were the 'best' BP cap available. Thanks for pointing it out.
     
  5. avionic

    avionic " Black Knights " Subscriber

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    Don't sweat it. The ES's look nicer..:D
     
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  6. Mr. Yamaha

    Mr. Yamaha Not so much Yamaha lately...

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    Yeah, defenitely love the look of the green ones. Almost as much as the golden FG’s and gold striped KZ’s :D
     

     

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  7. Oldsansui441

    Oldsansui441 AK Subscriber Subscriber

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    Nice work Mr. Yamaha, looking very good :thumbsup:.
     
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  8. mbz

    mbz AK Subscriber Subscriber

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    seconded.

    Also like Nichicon PW for the rest of the power supply board, not sure how the KZ(?) stand uo to the rigors of psu duties...

    Excellent work
     
  9. Oldsansui441

    Oldsansui441 AK Subscriber Subscriber

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    I generally use UPW's for power supply duties but have also used UKZ's in the past to try in this position and they stand up just fine.
     
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  10. mbz

    mbz AK Subscriber Subscriber

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    thanks for that, it's just that the data sheet does not include any ripple figures, under the impression they were mostly an audio path cap, certainly good.
     
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  11. Oldsansui441

    Oldsansui441 AK Subscriber Subscriber

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    Yes you are correct in everything you say, would be esp good if they included the ripple figures. I am sure they are a better quality cap than what was fitted to the power supplies originally, in most cases they didn't use a special cap for this purpose, usually the standard grey Elna's or the black Nippon Chemicon's.

    Here is an interesting read, patfont does lots of cap comparisons. Some people agree with him more than others but at least he has taken the time and effort to make comparisons within the same amplifier, something l would not have the time to do.
    http://audiokarma.org/forums/index.php?threads/electrolytic-capacitor-shoot-out.381961/
     
    Last edited: Jan 28, 2018
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  12. Oilmaster

    Oilmaster Drillers go deeper Subscriber

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    Common guys, pleazzzz don't make this into yet another "my favourite capacitor" thread.
    We have had enough of those.
    There are so many other details of (t)his rebuild that would be interesting to review instead
     
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  13. rottalpha

    rottalpha Yamaholic Subscriber

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    I am not that person you are reffering to, but I will second that sanding will damage the few microns of gold or silver plating Alps, not Yamaha, coated some of those switches.
     
  14. Mr. Yamaha

    Mr. Yamaha Not so much Yamaha lately...

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    And what do you think those copper sliders did to that layer the last 40 years going back and forth ;)

    I really doubt there is a special layer on the surface. Defenitely not gold. If it was on there, it wouldn't oxidize in the first place I guess :idea:

    I think I have to edit that earlier post, I changed the way of work after that. I now use de-oxit 100 and a glass fiber pen. No more wet sanding. And I leave the copper sliders untouched, those are never oxidized in my experience.

    Today's results of a slider switch from the meter board:

    Before:

    IMG_1169.jpg IMG_1170.jpg IMG_1171.jpg IMG_1174.jpg IMG_1175.jpg IMG_1176.jpg

    After:

    IMG_1177.jpg IMG_1178.jpg

    Fresh Fader lube on it:

    IMG_1180.jpg
     
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  15. rottalpha

    rottalpha Yamaholic Subscriber

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    I would do a bit more research before making these assumptions. Hint: nothing in there is pure copper.

    here is same basic switch:
    IMG_20170707_112600741_HDR.jpg
    IMG_20170707_115420974_HDR.jpg

    IMG_20170701_235050863.jpg
    IMG_20170702_000445477.jpg Screenshot_20170821-010834.png

    I know I need to invest in a better camera. I cleaned these using NO sandpaper and no fiberglass pens.
    I am no expert and I am certainly no chemist, so someone with more knowledge would need to opine, but I do not think that what we are cleaning is just oxidation. Lots of it I think is the original lube coating that has reacted to heat and....time.
    As far as Alps platng their switches and pots with precious metals, please do some research. Yamaha, Sony and other Japanese companies, used them in their 70's products and are still used today in high end proucts...nope not a marketing gimmic. As a matter of fact, the B-1 PCB / edge boards are gold plated and so are the pins ans pins connectors on some of the C-1s. The ones that are not gold plated are silver plated instead.

    EDIT: I think you are doing a fenomenal job with the restauration. I am just saying that there are different ways to clean those moveing parts..that is all.
     
    Last edited: Jan 28, 2018
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  16. rottalpha

    rottalpha Yamaholic Subscriber

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    I should have added that my first job ever (ages ago) involved for the most part cleaning pots and switches for an old school audio shop, but that is all.
     
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  17. Mr. Yamaha

    Mr. Yamaha Not so much Yamaha lately...

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    Thank you Pete, for your concerns and tips, highly appreciated :thumbsup:

    When knowledge is not available, assumptions will be made and ways of working will be figured / tried out :D

    I really believe you about that companies like Alps were and are using precious metals in there switches, but I don't think in all Alps switches Yamaha has used in the past have gold or silver in them. To my knowledge (again, limited) gold will not oxidize or react with other substances / materials.

    Maybe the used cobalt or nickel in some switches? I don't know. The best solution is to send som parts to a lab and let specialists figure out what kind of metals and coatings are used. But that would be a bit expensive I guess :naughty:
     
  18. rottalpha

    rottalpha Yamaholic Subscriber

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  19. rottalpha

    rottalpha Yamaholic Subscriber

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    Hi Guys,

    all I am saying is that these switches are plated with eiteher, silver, gold or a combination of the two. Most likely the later. I am saying this based on my observations, not because of some scientific study.

    please try this experimant:

    take an uncleaned switch, use a plain jane eraser and rubb an area clean, than take the sand paper and rub right next to it. In my experince, you will have two colors afterwords.
    I know my camera sucks, but the contacts of my switches still have a gold patina to their color. If I were to uese sand paper, they start to look silver...just saying.

    I am definetly not talking about relay contacts, component pins or PCBs, those are also plated for some components, which suppoets the hypothesys that even though plating with precious metals is expensive, certain manufacurers will do it for certain products.
    Back to the swithces,
    these are not pots, but low power switces. eve though they are physically linear, they have clearly divided points of contact.

    I did not have time to look for speciffic models or Alps examples, just a quick search on the net. Here is a quick article, but there re many more explaininng why manufacurers would use precious metal aloys on certain low current or data switches.

    http://www.nkkswitches.com/pdf/switchcontactmaterial.pdf

    again, I could be tottally wrong about the material, but as far as the plating, my hypothesys is that it is there.

    Edit:
    one additional observation,

    let's say I am tottally wrong and there is no plating on any of these contacts, still, wouldn't sand paper or fiberglass pen alter the physical surface?
     
    Last edited: Jan 29, 2018
  20. Oilmaster

    Oilmaster Drillers go deeper Subscriber

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    I guess you are making a point :rolleyes:
     

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