1. Time for some upgrades in server hardware and software to enhance security and take AK to the next level. Please contribute what you can to sales@audiokarma.org at PayPal.com - Thanks from the AK Team
    Dismiss Notice

Marantz 250 help

Discussion in 'Marantz Audio' started by Cumminscider, Nov 5, 2018.

  1. Cumminscider

    Cumminscider New Member

    Messages:
    17
    Was listening to music then one channel cut out and I saw this part arcing in the area circled. I shut it off and let it sit awhile, tried turning it back on the protection relay doesn't click anymore? Not sure what to check any ideas?
     

    Attached Files:

     

    Please register to disable this ad.

  2. bktheking

    bktheking Gitter Done! Subscriber

    Messages:
    12,864
    Location:
    Ottawa Ontario
    Arcing-large amounts of dc , relay won’t click cause the amp is probably in protection.
     
  3. Cumminscider

    Cumminscider New Member

    Messages:
    17
    Anything I can check with a voltmeter? I can't find any burnt parts, visually everything looks okay.
     
  4. ConradH

    ConradH Addicted Member

    Messages:
    7,931
    Location:
    Canandaigua, NY
    The Marantz 250 is a nice sounding amp, but the design is fraught with problems. Fixing it (and applying the essential upgrades) is not for the inexperienced and you've almost certainly got way more trouble than can be fixed with a DVM. Suggest locating competent tech (maybe somebody here on AK) ASAP.
     
    Cumminscider likes this.
  5. wlhd1610

    wlhd1610 Penny and her new friend Sponsor Subscriber

    Messages:
    2,535
    Location:
    Catskill NY
    ConradH is 100% correct.

    There are no less than 6 Marantz Technical Service Bulletins trying to address the issues that the 250 had.

    I'm doing one right now that had this happen....


    [​IMG]

    [​IMG]



    Bob
     
  6. ConradH

    ConradH Addicted Member

    Messages:
    7,931
    Location:
    Canandaigua, NY
    As Norm Abrams always said on his TV show, "And always wear these, safety glasses!"
     

     

    Please register to disable this ad.

  7. spark1

    spark1 Super Member

    Messages:
    1,479
    Location:
    The Great Midwest
    I assume you have no daughters.
     
  8. ChrisMarantz

    ChrisMarantz AK Subscriber Subscriber

    Messages:
    2,539
    Location:
    San Francisco Bay Area
    [​IMG]

    [​IMG]

    Awesome Failure - Chris
     
  9. tranguru

    tranguru Active Member

    Messages:
    201
    Location:
    Brussels
    Maybe just a bad elecro cap - but I doubt it....
    probably need to check for DC on the outputs...
     
  10. bktheking

    bktheking Gitter Done! Subscriber

    Messages:
    12,864
    Location:
    Ottawa Ontario
    Black to chassis ground, red to pin 5 and then 7 on the relay board- DC. Tell us what you read. Pin 5 in one channel, 7 is the other.
     
  11. bktheking

    bktheking Gitter Done! Subscriber

    Messages:
    12,864
    Location:
    Ottawa Ontario
    Bad electro cap with arching? I doubt it too.
     

     

    Please register to disable this ad.

  12. airtime

    airtime Super Member

    Messages:
    2,181
    Location:
    Central Arizona
    The 250 may look simple to fix but it's not. They worked very well with few problems. HOWEVER!!! once they needed to be fixed that's when the problems in the design become VERY apparent. You WILL need a skilled tech to not only fix it but do the upgrades and testing to undo the unstable design flaws.

    This is not a simple put in some caps and a transistor fix.
     
  13. ChrisMarantz

    ChrisMarantz AK Subscriber Subscriber

    Messages:
    2,539
    Location:
    San Francisco Bay Area
    The mantra for a Model 250 repair / rebuild / update has to be "Complete and Thorough with the greatest attention to detail" otherwise the end result will be a soft but unmistakable "poof" - Chris
     
    catrafter and wlhd1610 like this.

Share This Page