Yamaha CX-1 Thread

Discussion in 'Yamaha' started by Bratwurst7s, Sep 30, 2017.

  1. Karl vd Berg

    Karl vd Berg Super Member

    Messages:
    1,949
    Those ES 47µF/35v... just out of curiosity, James, what's the date printed in the sleeve? Also for the FM's and FC's?
     

     

    Please register to disable this ad.

  2. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    Hi Karl,

    ES 47µF/35v = H1737. I hope you can decipher that. :) Can that be (20)17 Week 37?
    FG 330µF/25v = H1625.
    The FM have no code printed on them and/or the Mouser label.
    Which FC do you want?
    47µF/50v = 65IIGL (almost impossible to read, not completely sure if that is a G, C or another 6)(the "II" and "III" are Roman Numeral 2 and 3)
    2200µF/35v = 01IIITM01III1M. Whatever that means.

    Out of curiosity I just dug through my bench stock and looked at some older ES caps bought from DigiKey. DigiKey is nice enough to print a date on the packing label.
    ES 100µF50v, code H1419, bought 13-April-2016 = 102.8µF, 0.06ohms, 1.0% vLoss. 8 pieces, all measured similar.
    ES 47µF/25v, code H1439, bought 8-May-2015 = 48.92µF, 0.22ohms, 1.7%. 2 pieces, measured similar.
    ES 47µF/16v, code H1440, bought 8-May-2015 = 47.7µF, 0.46ohms, 2.1%. 10 pieces, all measured similar.
    ES 22µF/25v, code B1406, bought 8-May-2015 = 26.42µF, 0.92ohms, 2.6%. 14 pieces, all measured similar.

    So it seems more like I'm seeing more of a variation in the values of particular production lots than age. All of the groups of caps that I've measured were very similar in their groupings/lots. This has been interesting.

    More later,
    James
     
    Karl vd Berg likes this.
  3. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    And now some film caps to compare. All Wima MKS 2 except for the 0.33µF, I still have a bunch of Panasonic ECQ in that value. About 1/3 of the caps measured showed no vLoss even after several tries. The highest shown was 0.1%.

    10µF/50v 10%, 7 pieces.
    Low/high µF = 9.01 / 10.05µF, Avg = 9.6µF.
    Low/high ESR = 0.02 / 0.07ohms. Avg = 0.38ohms.
    Low/high vLoss = 0.1%.

    10µF/50v 5%, 5 pieces.
    Low/high µF = 9.72 / 9.85µF. Avg = 9.78µF.
    Low/high ESR = 0.03 / 0.06ohms. Avg = 0.04ohms.
    Low/high vLoss = 0.1%

    2.2µF/63v 5%, 10 pieces.
    Low/high µF = 2.18 / 2.29µF. Avg = 2.23µF.
    Low/high ESR = 0.08 / 0.1 ohms. Avg = 0.085 ohms.
    Low/high vLoss = 0.1%.

    1µF/63v 5%, 10 pieces.
    Low/high µF = 0.964 / 1.01µF. Avg = 0.99µF.
    Low/high ESR = 0.22 / 0.26ohms. Avg 0.236 ohms.
    Low/high vLoss = 0.1%.

    0.22µF/63v 5% Just measured a few, they were all similar.
    0.224µF, 1.4 ohms, 0.1%.

    0.33µF/50v, Just measured a few, they were all similar.
    0.322µF, 0.8 ohms, 0.1%.

    I just made another Mouser order.
    MKS-2 in 10µF, 4.7µF and 3.3µF (5%).
    KL in 470µF/50v, 330µF/25v, 100µF/35v and 47µF/35v.
    KZ in 47µF/50v.
    FM in 470µF/25v, 470µF/50v, 330µF/25v and 330µF/35v.

    Cheers,
    James
     
    Beau Geste likes this.
  4. Karl vd Berg

    Karl vd Berg Super Member

    Messages:
    1,949
    I believe you are right in case of Nichicons. The first letter (B, H, etc) may be the plant/factory/country of origin...

    Nichicon has been using this code system since the 70s

    [​IMG]

    [​IMG]

    The FC date code is another story, but probably @Oilmaster knows something about them... :)
     
    Bratwurst7s likes this.
  5. Oilmaster

    Oilmaster Drillers go deeper Subscriber

    Messages:
    1,212
    Location:
    Paris & The Hague
    see page 2 of this document for Panasonic date coding
     
    Karl vd Berg and Bratwurst7s like this.
  6. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    Thank you Karl and Oilmaster.

    There is nothing worse than spending weeks waiting for parts.
    Today I ordered a second set of the Mundorf 6800µF caps from Banzai. Getting tired of waiting on Bürklin.
    At least only a few hours after I closed my Mouser order they posted that the parts have shipped. Should be here on Wednesday.
    The service manual is supposed to be getting close to getting here.
    My fingernails are getting short.

    Cheers,
    James
     

     

    Please register to disable this ad.

  7. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    My last Mouser order arrived. And Banzai wrote today that the MLytic filter caps have shipped. The service manual is at least somewhere here in Germany now. I don't know if it will come direct or if I'll have to go to Customs to pick it up.

    At least things are inching forward.

    Cheers,
    James
     
    Last edited: Jan 5, 2018
    808_state likes this.
  8. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    The service manual arrived today, along with a SM for my AX-1090 and oh(!), a SM for the MX-1/MX-2. ;) I don't have a MX-1, but one never knows what might develop with this new year.
    DHL wrote that my Banzai order is supposed to be delivered Monday.

    I may just start working on this thing tomorrow.

    Cheers,
    James
     
  9. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    So yesterday I had a nasty headache so I kept my fingers away from the system. Except to use it. I've become seriously attached to this pre-amp.

    But today after one more listening session I pulled it and put it on the workbench. One thing that I forgot to mention before is the volume and input selector knobs. Unlike all of the allu sleeve over a plastic knob like I'm used to seeing these knobs were turned from solid bar stock and only have a small plastic center bushing to mount to the shafts. They have a bit of weight to them.

    DSC04695.jpg DSC04697.jpg DSC04698.jpg DSC04699.jpg

    Cheers,
    James
     
    Beau Geste likes this.
  10. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    After removing the front cover I got an interesting surprise. The input selector shaft is stabilized with a bushing turned from solid brass. And the volume and rec-out shafts have a bushing cut from solid brass hex-bar stock. Serious stuff here.

    I decided to start out small and removed the volume/selector pcb first. That's as far as I got today. Tomorrow I'll work on that board.

    DSC04701.jpg DSC04702.jpg DSC04711.jpg DSC04712.jpg

    Cheers,
    James
     
    Beau Geste likes this.
  11. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    Since it's Monday I'm starting out slow and easy. Today I only did the volume/input selector board. Replaced the 8 caps and reflowed all of the connections.

    In the end I decided to use an FM in 50v for the 100µF and KL's in 35v for the 47µF in the signal path. The old caps measured as follows (µF, ESR, vLoss)...

    C562: 100µF/16v = 91.5µF, 0.88 ohms, 2.5%.
    C554: 47µF/16v = 47.4µF, 1.4 ohms, 2.5%.
    C555: 47µF/16v = 47.5µF, 1.4 ohms, 2.5%.
    C558: 1µF/50v = 1.02µF, 6.0 ohms, 1.2%. Date code A9304.
    C563: 1µF/50v = 1.02µF, 6.0 ohms, 1.0%.
    C557: 1µF/50v = 1.01µF, 6.0 ohms, 1.2%.
    C559: 1µF/50v = 1.03µF, 5.9 ohms, 1.3%.
    C564: 0.33µF/50v = 0.32µF, 7.0 ohms, 0.7%.

    I've also been measuring the last batch of new caps that Mouser sent. I'll post the results as the week flows.

    We have a scanner at work that can do DIN A3 sized color scans in 600dpi. Not the best res but still not bad. I scanned the board layout pages and schematic today. The board layout pages came out in 1 scan. A friend that is pretty good with photoshop is going to try his hand at stiching together the 4 scans-per-side of the schematics. All in all they look enormously better than the SM at HiFi Engine. I will submit the results to the AK database when it's finished.

    So it's now Day-1 without listening to this thing and I'm already starting to get nervous. By tomorrow my hands will be shaking...

    DSC04713.jpg DSC04714.jpg DSC04715.jpg DSC04716.jpg DSC04718.jpg

    Cheers,
    James
     
    Last edited: Jan 15, 2018
    Beau Geste likes this.

     

    Please register to disable this ad.

  12. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    I seem to recall reading in another thread that you recently bought a leakage tester. Since I have a collection of various new caps would you like me to sent you some samples to test? You could add them to your collection of caps afterwards. :)

    Cheers,
    James
     
  13. Oilmaster

    Oilmaster Drillers go deeper Subscriber

    Messages:
    1,212
    Location:
    Paris & The Hague
    Hi James,

    Yep, the thing is one its way from the other side of the planet to my place.
    Should arrive by the end of January (as fast courier shipping would cost me dearly)

    No problem to measure your caps; always interesting.
    We'll PM later then

    cheers,
    Oscar
     
    Bratwurst7s likes this.
  14. Karl vd Berg

    Karl vd Berg Super Member

    Messages:
    1,949
    Hi James,

    Was that old cap an electrolytic one? Just curious to know if the film one have similar ESR value (if you have measured it before)...

    Cheers.
     
  15. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    Hi Karl. :)

    All 8 caps were elcos. All of the caps that I'm planning on replacing are elcos.

    I only measured a few of the Panasonic ECQ's but this is representative...
    0.33µF/50v, Just measured a few, they were all similar.
    0.322µF, 0.8 ohms, 0.1% vLoss.

    So in rough terms, a major improvement with the film caps. Look above at post #123.

    Cheers,
    James
     
  16. Karl vd Berg

    Karl vd Berg Super Member

    Messages:
    1,949
    From the 7 ohms of ESR from the old elco to 0.8 ohms of the ECQ's is pretty good improved number! :)
    Just wondering why Yamaha used an elco in that position... and curious to hear about the results.

    Cheers
     

     

    Please register to disable this ad.

  17. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    Well, that 0.33µF and the 1µF's are only doing duty for the voltage regulator for the motors, so it would have no sonic impact. But it will be interesting to see what condition the other small caps are in. Those that will would have a sonic impact, like that 2.2µF in the 0-db amp.

    Cheers,
    James
     
  18. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    Sounds great Oscar, thanks! It would be cool to see a "Capacitor Leakage Reference" thread. :) ;)

    Cheers,
    James
     
  19. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    Today I was able to recap the 20-DB Amp, Tone Control and Phones drive board.

    As with the volume section I decided to use KL in the signal path except for the small caps where I used MKS2. For C518 and 519 I used the FC 2700µF/35v to replace the 2200µF/25v. There was just enough room to shoehorn a pair of MKS2 10µF/50v for C531 & 536 in the Phones drive, which look to me to be in the signal path.

    There is a discrepancy concerning the 2x 330µF/16v caps in the Tone Control section.
    The schematic shows both caps with their plus leads on the traces leading to the op-amp IC503. The caps were OEM installed with their minus leads on the traces leading to that op-amp.
    For C544 the pcb silk screen matches the way that the cap was installed.
    For C539 the pcb silk screen is backwards to the way the cap was installed.
    The SM board layout drawing shows the caps the way that they were actually installed.
    I used Nichicon KL 330µF/25v here.

    Other than that the recap of this board went straightforward. I'm happy to have been able to have replaced 10 elcos on this board with film caps. That totals 15 so far.

    I haven't measured all of the old caps yet, just the 20-DB amp section so far.
    C518: 2200µF/25v = 2168µF, 0.08 ohms, 2.9%.
    C519: 2200µF/25v = 2168µF, 0.07 ohms, 2.5%.
    C517: 47µF/25v = 46.01µF, 0.71 ohms, 2.5%.Date code: H9128.
    C520: 47µF/25v = 45.79µF, 0.77 ohms, 2.6%.

    The tape used to tie the larger caps together was still sticky enough to be re-used, so I did.

    That's all for tonight. The plan for tomorrow is to reflow the rest of the connections on this board, measure the rest of the old caps and work on documenting things.

    DSC04726.jpg DSC04728.jpg DSC04729.jpg DSC04730.jpg DSC04731.jpg

    Cheers,
    James
     
    Last edited: Jan 15, 2018
    Beau Geste likes this.
  20. Bratwurst7s

    Bratwurst7s In The Frying Pan Subscriber

    Messages:
    3,918
    Location:
    Munich, Germany
    DSC04732.jpg DSC04733.jpg DSC04734.jpg

    edit: I didn't notice this earlier. Flanking the dual buss bars on the left side of the last photo. 4 (!) unobtanium 2SK389 dual FETs.
     
    Last edited: Jan 10, 2018

Share This Page