Marantz 2245 voltage adjustment problem

Discussion in 'Marantz Audio' started by AngelAT, Jul 13, 2018.

  1. AngelAT

    AngelAT Member

    Messages:
    91
    Hello everybody!

    I have a Marantz 2245 - i believe that it might be from the first productions (1001-3600). What makes me think like this is the fact that my unit does not have a main fuse at the back. (BTW i can not check the number because the Marantz plate at the back is missing...)

    The story:
    I partially restored the phono board p700 - i changed c713 with nichicon 100 mF/50V, h707/708 and h709 with 1n4148 x4. And I changed the notorious h705/706 with 2sc2240. After finishing I powered the unit and i think there was no problem.

    I cleaned the contacts of the relay and recapped the power supply board - mainly with nichicon. I only put some other brand at c802/804. When I powered it up the relay ticked and after that there was some smoke coming (I think) from around c803/804. That is why i returned the original c803/804. There was no smoke and the relay is ticking.

    The problem:
    When I started to adjust the voltage (I connect to j802 and j803) and the DVM shows 44 volts. When I turn r809 there is no change at all.

    What have I done wrong?
    How can I fix this problem?

    Any ideas are welcome!
    If you need further info, pls ask.
    Thanks in advance!
     

     

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  2. wlhd1610

    wlhd1610 Penny and her new friend Sponsor Subscriber

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    Are you saying you changed each one of the H707/708 and 709 with four 4148's in series or between the three you used a total of four 4148s ?

    Bob
     
  3. petehall347

    petehall347 the brandy coffee man Subscriber

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    The problem:
    When I started to adjust the voltage (I connect to j802 and j803) and the DVM shows 44 volts. When I turn r809 there is no change at all.

    What have I done wrong?
    How can I fix this problem?

    look at the schematic first maybe ?
    tell us where each meter probe was . i can only guess its between those 2 places .
    if trying to set 35v go from chassis ground to j802 .. am sure this will be in error thread .
     
  4. AngelAT

    AngelAT Member

    Messages:
    91
    Hi Bob,

    Thanks for the quick response!
    I used total 4. Two in series for h709.

    Angel
     
  5. AngelAT

    AngelAT Member

    Messages:
    91
    Hi Pete,

    These two places were specified in the service manual. So one of the probes was at j802 and the other at j803. Looking at both schematics (for old and newer versions) I do not see any differences around j802 and j803 in p800.
    Any ideas?

    Angel
     
  6. AngelAT

    AngelAT Member

    Messages:
    91
    I checked the different pin voltages and this is what came out:
    -j804 and j805 = nothing
    -j803 and j806 = 33 v
    -j801 and j803 = 13,1 v
    -third terminal strip b/n phono and tone board = 34 v

    Angel
     

     

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  7. petehall347

    petehall347 the brandy coffee man Subscriber

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    there are errors in the manuals . but this time its not wrong .
    j804 j805 are AC voltages .

    h805 might be shorted emitter to collector . best check it .
     
  8. AngelAT

    AngelAT Member

    Messages:
    91
    Thanks Pete,
    Actually it came to be h806.
    I read that I can replace it with 2SC2240.
    Is this OK?
     
  9. AngelAT

    AngelAT Member

    Messages:
    91
    One more thing:

    From the data sheet of the c734 (y) I saw that pins are B, C, E.
    But it was put vise versa from what is printed on the board (? IMG_20180714_001155[1].jpg View attachment 1235210 IMG_20180715_111642[1].jpg )
    Is it possible that there is a mistake and more important:
    How to place the replacement?

    Thanks!
    Angel
     
    Last edited: Jul 15, 2018
  10. petehall347

    petehall347 the brandy coffee man Subscriber

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    was it original ?
     
  11. AngelAT

    AngelAT Member

    Messages:
    91
    the c734?
    I have no idea, but should be.
     
    Last edited: Jul 15, 2018

     

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  12. AngelAT

    AngelAT Member

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    I placed the c2240 the way c734 was placed.
    And smoke came from r804

    Any ideas?
    Thanks!
     
  13. petehall347

    petehall347 the brandy coffee man Subscriber

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    2sc734 is ecb .. board layout agrees with schematic
    2sc2240 should be ecb as well .
     
  14. AngelAT

    AngelAT Member

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    91
    ok, maybe I found the wrong info.

    Is 2sc2240 a good replacement?
    thx!
     
  15. petehall347

    petehall347 the brandy coffee man Subscriber

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    Will look later sat in hospital waiting to have my foot looked at it swelled up .
     
  16. EastPoint

    EastPoint Factory Code No. 4200 Subscriber

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    I believe the KSC2383 is a good sub for the 2SC734. Not sure about the 2SC2240.
     

     

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  17. AngelAT

    AngelAT Member

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    Get well soon Pete!
     
  18. AngelAT

    AngelAT Member

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    Thanks!

    Will look at the specs.
     
  19. petehall347

    petehall347 the brandy coffee man Subscriber

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    even with the 2240 in there that resistor should not have smoked . looks to be to limit current through h805 .
    what fault did h806 have ?
     
  20. AngelAT

    AngelAT Member

    Messages:
    91
    h806 was shorted between E and B.
    Should I replace h805?
     

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