2230 - P400 Board Mislabeled - Need Help?

Discussion in 'Marantz Audio' started by milanomike, Mar 7, 2018.

  1. milanomike

    milanomike Active Member

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    On my 2230, I believe a transistor has gone out creating ugly noise thru the left channel. This is on the P400 board. So, I've decided to replace all 8 transistors (and caps once I verify it works), but I am not savvy enough to sort thru and determine equivalent replacements. I've read tons of threads but have not clearly identified replacements. Do the transistors need to be matched for this board?

    Finally, my board appears to be mislabeled, I have attached a photo of the board, hope it shows OK. There are 2 H402's shown (on left and right with left being top in the photo) by studying the parts list I believe the H402 on the right should be H403 (2SA493GR) and the H403 or the left (top) should be H404 (2SA493GR). I base this on logic from the other channel on the board. Does this make sense?

    H401 - 2SC1000BL
    H402 - 2SC1000BL
    H402 right side should be H403 or 2SA493GR
    H403 left side should be H404 or 2SA493GR
    H405 - 2SC1000BL
    H406 - 2SC1000BL
    H407 - 2SA493GR
    H408 - 2SA493GR

    I need to identify the correct equivalents here so any help is appreciated. Don't want this post to be too long, so cap question saved until I sort this out. Thanks.

    Mike


    t 2230 P400 Board.JPG
     

     

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  2. Jailtime

    Jailtime Standin' on a corner Subscriber

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    Not surprising that a Marantz board is mislabeled, you'll see it dozens of times if you dig through enough of them. The phono channels are mirrored, so your logic makes sense to me.

    2SA493 can be replaced with KSA992, 2SC1000 with KSC1845. Make sure the pinouts are correct. I haven't matched phono transistors, but if you're doing a fancy rebuild, why not?
     
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  3. MBuras

    MBuras Restoration is an Addiction Subscriber

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    The mislabeled H402 is well documented on the service manual error sticky at the top of this forum. You can also search that thread for other 2230 errors should you decide to dig in and do additional work on your 2230.

    Mike
     
  4. quaddriver

    quaddriver 120 What's per channel Subscriber

    IIRC on the P400, the phono board has essentially 2 stages and the trans suffix indicated stage2 was 'gain-ier' than stage 1. So i matched Left to Right both times, and made stage 2 matched a few points higher. granted, since I got my 992's/1845s by the 1000 (literally) high to low was generally 20 points so stg 1 might be '400' and stg 2 might be 420.

    in the end, all rude behaviour and noises were gone.

    there is also a cap and resistor mod for the 2230 phono board. look up the reply from catrafter to my thread 'cantankerous 2230', he posted the before/after SCM of the mod.
     
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  5. patfont

    patfont AK Subscriber Subscriber

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    FYI P400 is the "Preamp" board.
     
  6. quaddriver

    quaddriver 120 What's per channel Subscriber

    yes, phono preamp, sometimes referred to as the RIAA EQ board, but phono amplifier in the 2330 SCM/SM
     

     

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  7. milanomike

    milanomike Active Member

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    Thanks for great input, stuck at work now, so have more reading to do. My Fluke does not check HFE, but my free Harbor Freight meter does, is this adequate or should i score something a bit better? Will check sticky also.
     
  8. milanomike

    milanomike Active Member

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    Had a few mins here and googled KSA992 for kicks.

    Do I need to worry about letters after 992, i.e. Mouser shows 4 types in stock, KSA992FTA, KSA992FBTA, KSA992FBU and KSA992FATA.

    There seems to be some differences, i am guessing the ones that show the operating temp range of -55 to 150 C are the ones i want?

    Thanks again.
     
  9. rBuckner

    rBuckner Luv 2 Restore Subscriber

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    The "TA" on the end means they are taped for automated assembly equipment and the "BU" means bulk. The F, FA and FB specify what gain range the parts are and any of them are fine for this circuit. Check out the data sheet link on Mouser for further study. Hope it fixes it!
     
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  10. patfont

    patfont AK Subscriber Subscriber

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    I like to order 100 each of the taped, they tend to be pretty consistent HFE in case you need to match for some reason in the future.
     
  11. Steven Tate

    Steven Tate AK Subscriber Subscriber

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    Just to be clear, the P400 board on the 2230 is the Tone Amplifier/preamp. P400 on the 2330 is the phono preamp. Marantz found another way to be confusing.:eek:
     
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  12. milanomike

    milanomike Active Member

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    Everyone, thanks for the help. I found the service manual error listing and yeah, the error was listed there. I've read tons of threads trying to learn and never found that.

    rbuckner: thanks for the education on transistor labeling/packaging

    quaddriver: not clear on how many 45 ohm resistors to add - thinking I need this to work first, will study thread in more detail, but what does this do?

    OK, I can order transistors at Mouser, etc., now that I understand better. Thinking I'll buy a few of each and check HFE to see what I learn.

    My simple brain says, I should do the caps as well, once she works. I somehow just found the cap list here on AK with Digikey p/n's listed! Of course, I will double check what is in my unit.

    One dumb question though, what is the difference between all the different classes of capacitors made by Panasonic, Nichicon, Elna? How do I determine what I need?

    I also plan to do the power supply board and the big caps, first things first though, need the big bad buzz I think is coming from P400 gone.

    Mike
     
  13. Steven Tate

    Steven Tate AK Subscriber Subscriber

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    This board is loaded with small caps that are frequently replaced with WIMA film caps. The photo below shows the abundance of red WIMA films. The big white EVO oil caps at the bottom were an experiment to see if I could hear the difference in premium caps like these or standard Panasonic polypropylene caps. I couldn't and I don't use the EVO oils any more. The WIMA films are non-polar, so they can go on the board either way. The few electrolytics left can be replaced with something like Elna Silmic II's or Nichicon KL or FG series. I'm sure others have their preferences. I'm no expert on the theory. I have just seen these caps used on this board with success.
    Steve

    IMG_1281.JPG
     
  14. quaddriver

    quaddriver 120 What's per channel Subscriber

    i didnt see the dif...I wanted to talk about the correct 2230 machine, but referenced the 2330 SM!

    oddly, I think the same relationship exists on either board...2 stages with different gains and I have done each the same way
     
  15. quaddriver

    quaddriver 120 What's per channel Subscriber

    ok, since its in my brain that this is a 2230...re-check out my thread on the cantankerous 2230 - it had hum introduced all over, I have found in my limited marantz experience that the pre-B machines are ground loop nightmares and very susceptible to outside noise...right now yours is on the bench, metal covers off, and your phone and likely laptop are close by - that alone is gonna skew any listening results. these will never be shot into space and expected to work!

    On the lower power units, marantz had a bad habit of separate ground planes *on the same board* at times. (driver/amp board can have 3 planes that dont meet until a foot of wire later) recheck any ground points, flow them and on any and all pre-out, main in setups, bridge the signal pin AND the ground. there is some good dang chalk talk as to why not having the ground here causes buzz, I found it was due to a loop set of patch cords with no ground

    AND check out signal feed lines, the ones where the center in plastic is the signal and inside the insulation is a wrap, it is generally connected on one end to minimize RFI and not cause a loop condition AND are you finding this buzz when playing TT? when I was testing I was using the customer pioneer PL45 which during arm movement shorts the coils R/L+ side with a zero ohm copper strip. During arm movement, the marantz interpreted this as a perfectly good AM noise generator. test using like a 500+ ohm resistor plug to short +/- of the phono inputs - if that is where this is happening.
     
  16. milanomike

    milanomike Active Member

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    Steve - thanks for the clarification, i had seen a thread with these WIMA film caps, didn't quite understand they could replace the small caps.

    Quaddriver - will check all grounds and solder joints.

    I think i have enough info to get my order together this weekend, just need a bit of time to play with it.

    Will report back.
     

     

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  17. milanomike

    milanomike Active Member

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    OK, ready to order the transistors and caps for P400. Just to double check myself and all my reading I will replace all 1 uF and 3.3 uF electrolytic caps with these WIMA's. The WIMA's are not polar so no need to worry about direction on installation.

    https://www.mouser.com/ProductDetail/505-MKS2B041001C00KS

    https://www.mouser.com/ProductDetail/505-MKS23.3-50-10

    Since order is not much, I am adding the caps & diodes for the PS board to round out the order from Mouser, found the diodes listed here:

    http://audiokarma.org/forums/index.php?threads/marantz-2230-restoring-it-from-scratch.761703 - they check with my unit - so far so good.

    I have decided to order the main big caps since I'm here, and my head started swimming, again!

    This thread: http://www.audiokarma.org/forums/in...-at-a-really-nice-rebuild-marantz-1060.489269

    states to go with 2 at 6800 uF, 63 volts & 1 at10000 uF, 100 volts. To me these are big increases over stock.

    Will this be OK and not lead to thumps during start up or other issues, they appear to fit the clamps.

    My goal is to have this unit make music

    Thanks again for the help.
     
  18. Steven Tate

    Steven Tate AK Subscriber Subscriber

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    The WIMAs look good. You might have to lengthen some leads on a couple of them to make them fit. I have used those bigger caps as recommended by some of the experts and they worked great. The caveat is that I rarely use that unit, so can’t say if there might be some down side with daily use. Hopefully others will chime in with opinions.
     
  19. milanomike

    milanomike Active Member

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    Steve, once again thanks for the info.
     
  20. milanomike

    milanomike Active Member

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    OK, finally got my bits ordered. So far a good learning experience, yeah I could have ordered a kit, but this way I get to study the options and learn a little as I go. One bit was backordered, but Mouser site says it arrives tomorrow, so maybe I'll see this stuff by the weekend if I'm lucky. I think I got it, but may have a question once I get in deeper with this. Hopefully, she will make music soon.
     

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