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Starting Marantz 2325 rebuild

Discussion in 'Marantz Audio' started by Steven Tate, Oct 6, 2016.

  1. MBuras

    MBuras Restoration is an Addiction Subscriber

    Messages:
    610
    Location:
    Urbana, IL
    Ah yes, the PU01 Blending board. Yuck! IIRC it's buried under the lighting and requires almost complete disassembly of the face to access. I remember a few choice curse words during that work.

    I replaced all 8 e-caps and 6 to-92 transistors, although none of them were trouble makers so not necessary. Back then I wasn't as focused on films and didn't replace those. Probably won't go back and do any further upgrades to that unit unless I can solve the dolby issue.
     

     

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  2. MBuras

    MBuras Restoration is an Addiction Subscriber

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    Not sure if this is helpful or just interesting info, but after 4 hours of steady playing the R719 resistor is definitely the hottest one on the amp boards. It's mounted vertical and the top edge is reaching temps over 90C! Toasty! The R801 resistor on the power board is still hitting 88C right in the middle. Also on the power board C809 and C805 are the warmest at 48C and 49C respectively.

    Seems to debunk the need for hi temp caps but those UPW's have the added benefit of outstanding ESR and ripple numbers so worth it.
     
  3. Steven Tate

    Steven Tate AK Subscriber Subscriber

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    Good info. I'll check those next time it's powered up. I just did the PH01 Buffer Amp Board using your restore thread. That's the one where CH13 is marked wrong on the board and you had an accident. Very likely saved me the same fate. These rebuild threads really are helpful. BTW, The only 220 uF 50V cap for CH13 I had was a KL series Nichicon. It's not rated at 105C like the rest, but this doesn't seem like a hot spot. Nevertheless, next time I place an order, I might get a few PW series of that value and replace it. Thanks again!
     
    Last edited: Oct 9, 2016
  4. MBuras

    MBuras Restoration is an Addiction Subscriber

    Messages:
    610
    Location:
    Urbana, IL
    Glad it was of use. Helped you. Did someone else a disservice with my error on the diodes. I guess it all equals out in the end. Funny thing is that every time I think my knowledge on these units has plateaued I learn something new and am humbled again. Probably a good thing.

    Seems like you decided to restore more than than just the power amps and power supply. Looks like it's coming along nicely. Keep up the great work. It'll definitely be your favorite receiver when finished.
     
    Last edited: Oct 9, 2016
  5. Steven Tate

    Steven Tate AK Subscriber Subscriber

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    N. Richland Hills, TX
    Yeah, I just kind of wandered into a semi-complete rebuild. I was so curious about how it was put together, as I disassembled things, I just kind of found myself in the position of, "well, while I'm here, might as well put in some new components". Lol.
     
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  6. Autobahn

    Autobahn AK Subscriber Subscriber

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    144
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    APO, AE
    No, looks like I missed doing PU01.
     

     

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  7. Steven Tate

    Steven Tate AK Subscriber Subscriber

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    I'm not sure it's worth it for 8 or 9 caps. :eek:

    Here are the parts I replaced (or am waiting on parts to replace) on the last three boards I have done

    P400 Phono Amp Board

    C401/402 1µF/25V - Panasonic 1µF/250VDC Mouser 667-ECW-F2105JA
    C403/404 47µF/16V - Nichicon ES 47µF/16V Mouser 647-UES1C470MPM1TD
    C413 100µF/35V - Nichicon HE 270µF/50V Mouser 647-UHE1H271MHD6
    (PW series was too tall for this spot) CAUTION! If replacing the axial cap with a radial, be aware that the + sign next to the two closely spaced lead perfs in the center does NOT indicate positive for those two perfs. It is actually close to the negative perf. Follow the silkscreened trace on the board to the negative side where the axial cap was attached and you will see.
    C414/415 1µF/250V - Panasonic 1µF/250VDC Mouser 667-ECW-F2105JA

    H405/406 2SC458 - Fairchild KSC1845FTA Mouser 512-KSC1845FTA (Watch pin order)
    H407/408 1S2473 - Fairchild 1N4148 Mouser 512-1N4148
    H409 VD1212 - Fairchild 1N4148 Mouser 512-1N4148 (Two connected in series)


    Ran out of the Panasonic 1uF caps., so have them on order for C414/415. Also the 270uF/50V is on order to replace the big axial cap.
    [​IMG]


    PU01 Multipath Blend Circuit Board

    CU01/02/04/ 4.7µF/35V - Nichicon KL 4.7µF/50V Mouser 647-UKL1H4R7KDDANA
    16/17
    CU03/21 10µF/16V - Nichicon KL 10µF/16V Mouser 647 UKL1C100KDD1TD
    CU20 47µF/35V - Elna Silmic II 47µF/50V Mouser 555-RFS50V470MH4#5

    No picture taken, and I'm definitely not going back in there!



    PH01 Buffer Amp Board

    CH05/06/07/ 4.7µF/35V - Nichicon KL 4.7µF/50V Mouser 647-UKL1H4R7KDDANA
    08
    CH13 220µF/35V - Nichicon KL 220µF/35V Mouser 647-UKL1V221KPD
    CAREFUL! The silkscreen is wrong on CH13. Negative should face the edge of the board

    HH01/02/03/ 2SC1345 - Fairchild KSC1845 Mouser 512-KSC1845FTA
    04
    HH09/10 2SC1318 - Fairchild KSC2383YTA Mouser 512-KSC2383YTA

    [​IMG]
     
    Last edited: Sep 23, 2018
  8. rBuckner

    rBuckner Luv 2 Restore Subscriber

    Messages:
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    Location:
    Prescott, Arizona
    On the glass small diodes I'd leave them in, whatever they are currently, if they work!

    No warning if an amp goes into oscillation. The one I had do that was a Sansui and I heard a funny loud screech and it went dark as the fuse had blown. I had just reworked a blown amp channel and used recommended replacement transistors and had just adjusted the bias to spec and kablooie. I finally figured out that for whatever reason, the bias needed dialed up higher due to the difference in the new transistors and I had not changed any resistors. I tried a few things to cool down the transistors like higher emitter resistors in the driver stage, higher value resistors on the bases and miller caps which are small value caps from base to collector. Nothing stopped it. So the bias was dialed up past stable a bit and the Sansui was still playing fine a few years later when I checked. Marantz amp design seems to be more stable. I probably shouldn't have mentioned the possibility and alarmed you!
     
  9. runningdog

    runningdog AK Subscriber Subscriber

    Messages:
    398
    Location:
    Sonoma, CA
    I used to curse the PU01. Sometimes I still do. But remove enough other parts and the PU01 is made accessible painlessly:

    1. Remove the tone board and the shield under it.
    2. Unscrew the power switch from the front chassis and push it out of the way.
    3. Remove the 6 screws holding the front chassis to the side chassis and gently ease the front chassis outward.
    4. Unscrew the PU01 from the front chassis.
    5. Push the switches back through the front chassis, holding the Multipath switch down as you go.

    Now the PU01 is hanging reasonably free and all the caps are accessible.
     
  10. Steven Tate

    Steven Tate AK Subscriber Subscriber

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    Location:
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    Looks like I did it the hard way. There is a shield behind the board that keeps it from moving back. Couldn't remove the shield, but I could slide it far enough toward the meter side to allow PU01 to slide back, tilt down and out the bottom. My biggest hang up was figuring out that the power switch had to be pushed out of the way. Your way sounds much better.
     
  11. Steven Tate

    Steven Tate AK Subscriber Subscriber

    Messages:
    2,956
    Location:
    N. Richland Hills, TX
    Moved on to the PL01 Dolby, Tone and Meter Circuit Board. Just a few caps on this little board. Didn't touch any other components

    After replacing all electrolytics (one on bottom of board)
    [​IMG]

    And the parts used:
    PL01 Dolby, Tone & Meter Circuit Board

    CL05/06/07 10µF/16V - Nichicon KL 10µF/16V Mouser 647 UKL1C100KDD1TD
    10/11/12/13
    CL/14 33µF/35V - Elna Silmic II 33µF/50V Mouser 555-AFS50V330MH4#5
    (Bottom of Board)

    Then the P300 FM MPX Circuit Board

    After replacing caps. Nothing else touched. Lots of these became WIMA films
    [​IMG]

    And the parts I used. Since I wasn't planning on doing this board originally, I didn't order any parts. Luckily, I had everything on hand, but some of the caps were Nichicon KL series. They are not 105 degree caps, but hopefully they will be OK in this location. If you see any glaring errors, or anything I should change, please let me know!

    P300 FM MPX Circuit Board

    C302 33µF/10V - Nichicon KL 33µF/16V Mouser 647-UKL1C330KDDANA
    C304 22µF/16V - Panasonic FC 33µF/25V Mouser 667-EEA-FC1E220
    C307 .47µF/50V - WIMA MKS2 .47µF/50V Mouser 505-MKS2.47/50/10T
    C308/309 .22µF/50V - WIMA MKS2 .22µF/63V Mouser 505-MKS20.22/63/5
    C323/324 .22µF/35V - WIMA MKS2 .22µF/63V Mouser 505-MKS20.22/63/5
    C325/326/ 1µF/35V - WIMA MKS2 .1µF/50V Mouser 505-MKS2B041001C00KS
    331/338
    C327 220µF/25V - Nichicon PW 220µF/35V Mouser 647-UPW1V221MPD6
    C328 220µF/16V - Panasonic FC 220µF/16V Digikey P11199-ND
    C329/332 10µF/16V - Nichicon KL 10µF/16V Mouser 647 UKL1C100KDD1TD
    C337 4.7µF/35V - Panasonic FC 4.7µF/50V Mouser 667-EEU-FC1H4R7
     
    Last edited: Oct 11, 2016

     

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  12. rBuckner

    rBuckner Luv 2 Restore Subscriber

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    Lookin' good! How is the Mrs. doing?
     
  13. Steven Tate

    Steven Tate AK Subscriber Subscriber

    Messages:
    2,956
    Location:
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    Thanks! Waiting on some parts I thought would come today, but no luck. Wife is doing better every day - finally not hurting all the time, just when moving around a lot. She sees the light at the end of the tunnel and that allows some mental healing too. Thanks for asking. :beerchug:
    Steve
     
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  14. Steven Tate

    Steven Tate AK Subscriber Subscriber

    Messages:
    2,956
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    P600 Dolby Circuit Board

    This one is a veritable pleasure to work on because the whole board comes out and you can work on it on the bench. Lots of 10uF caps on this one just like the tuners. Here is the board after replacing all electrolytic caps - nothing else - and the parts list. Had a shipping issue with the parts I'm waiting on. It's been five days since I ordered from Mouser, and they usually get here in two days. The Mouser warehouse is about 10 miles from here. After five days, no parts, so I checked the USPS tracking. The parts went from Mansfield (10 miles from me) to Ft. Worth (about the same) and then to Amarillo (300 miles away!) then finally back to Ft. Worth where they are now. I will probably get them tomorrow. The system obviously hiccuped on my parts. :mad:

    [​IMG]

    P600 Dolby Circuit Board

    C601/602 3.3µF/25V - WIMA MKS2 3.3µF/50V Mouser 505-MKS23.3/50/10
    C607/608/609 10µF/16V - Nichicon KL 10µF/16V Mouser 647 UKL1C100KDD1TD
    610/611/612
    613/614/623
    624/631/632
    635/636
    C627/628 47µF/10V - Nichicon FG 47µF/25V Mouser 647-UFG1E470MEM
    C641 220µF/25V - Nichicon KL 220µF/35V Mouser 647-UKL1V221KPD
     
  15. Steven Tate

    Steven Tate AK Subscriber Subscriber

    Messages:
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    Location:
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    I've pretty much finished the 2325. I went back and replaced the phono board caps I had ordered and I put the old 3W resistors back on the power amp boards. For some reason, I was having trouble getting the bias setting with the new resistors. Put the old ones back in and no problem. I have a final issue, though. Everything sounds great across the spectrum. But for some reason, when changing from FM to phono, there is a pretty significant volume difference. Phono has maybe half the volume of the tuner. If you turn the volume up, it sounds great, but that's not right. Could some of my cap or transistor replacements cause this? It's a new receiver for me and I haven't listened to it very much, but I did test the inputs before, and while the phono input had maybe 10% less volume than the tuner, there was not nearly as much difference as there is now.:dunno:
     
    Last edited: Oct 23, 2016
  16. KutzlerTrans

    KutzlerTrans Jennie & I with Buddy and Barney. Subscriber

    Messages:
    2,990
    Location:
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    Check your dolby volume settings.
    If your going through the dolby amp, it will be higher.

    Phono may be related to your needle pickup(Cartridge style). http://www.angelfire.com/wi/blueswapper/2325review.html

    if im reading this right, adding 20db head amp would bring it up. (mc cartridge)

    https://en.wikipedia.org/wiki/RIAA_equalization.
    A stand alone phono amp has RIAA built into it so it does NOT plug into the phono jacks, but is plugged into aux.

    Check this out
    http://www.vinylengine.com/step-ups-and-mc-cartridges.shtml
     
    Last edited: Oct 23, 2016

     

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  17. rBuckner

    rBuckner Luv 2 Restore Subscriber

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    Hmm, both channels are low. So what is in common? Two things come to mind, the first being the filter cap but as you know putting it in backwards smokes the 100 ohm resistor. Still, measure at both ends of the 100 ohm to see if it drops much voltage. The second thing that comes to mind is the diode replacement with the two in series. I went back and looked and couldn't tell what the polarities were. Other than that, a good inspection of the back side for soldering issues is in order. Something is amiss somewhere! (I don't think it was your component choices though)
     
  18. KutzlerTrans

    KutzlerTrans Jennie & I with Buddy and Barney. Subscriber

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    2,990
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    Thanks Master for the help. Caps are in right on the ph01 board. diodes are correct on the 400 board.
    I am not sure what h409 does, but i just looked up subs and it looks like two are fine. they look right, but i cant see the black ring on one.
     
    Last edited: Oct 23, 2016
  19. Steven Tate

    Steven Tate AK Subscriber Subscriber

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    Thanks for the starting points. I've been gone all day, but I'll dive in and check those things out. I use this turntable and cartridge (Dual 1229 with Shure M97xE cartridge) with lots of other Marantz receivers and it doesn't have this volume mismatch. It must be something I did. I'm going to check the Dolby settings first and then go through that phono board with a fine tooth comb.
     
  20. rBuckner

    rBuckner Luv 2 Restore Subscriber

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    I remember when a fine tooth comb would stick in my hair. Barely remember that is! :rflmao:
     

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