Märklin Marklin 8998 Turntable Info?

rray Jun 30, 2020

  1. rray

    rray Staff Member

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    I am sorting through my 16 year collection of Z Scale accumulate, and found I have a Marklin 8998 turntable, which looks complete. This is the original old style that has a blue control panel. I am going to clean it up and modify it for use, but there was no box or manual, and I don't know how to safely power it.

    There are 5 colored wires from the blue control box that plug in the underside of the turntable, Brown, Red, Green, Gray, and Yellow. Then there are 2 more gray wires that I assume are power, one with a black plug mini banana plug and one with yellow.

    So being that anyone could have removed and replaced the banana plugs on the gray wires I have to guess it's for AC power, because DC would need a bit more safety in choosing wire colors.

    Before I smoke it, does anyone know what the power requirements are? Also, does anyone have a list of what all the wires to the turntable are for? I have not yet taken this turntable apart.

    Thanks,
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  2. rray

    rray Staff Member

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    So I started cleaning everything up, and had to open the blue box in order to remove the knob so I can clean the aluminum panel, and much to my surprise, I found a huge bridge rectifier, telling me it runs on some sort of AC power. Either 10 or 12VAC I suspect.

    I also found a worn out and corroded wire wound rheostat, as well as a burnt resistor that cannot be identified but measures 15 ohms. Oh, joy! [​IMG]
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  3. rray

    rray Staff Member

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    So, what to use for a resistor? I want to limit the Marklin motor to 100mA current at 10V for maximum turntable speed.

    So I figure since I am using 12 VDC power for accessory, that probably measures 13.8 VDC. I can subtract 1.4 volts for the bridge rectifier since 2 diodes of the 4 will always be in use, that leaves 12.4V.

    I need to drop the max voltage to 10V, so ohms law math says if I want 10 volts divided by 100mA:
    10V /.1A = 100Ω so I need a 100 ohm resistor. Of coarse the rheostat will make it even lower, but full blast will not exceed 10V.

    Because there is a bridge rectifier in there, I can use a 12V AC or DC supply, and I don't need to concern myself with polarity.
     
  4. Fluegelmeister

    Fluegelmeister TrainBoard Member

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  5. rray

    rray Staff Member

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    Thanks Barry, I was surprised the manual just shows connections to a Marklin power pack but no other info like specs or anything. Clearly, the blue controller is nor DCC friendly.



    I'm taking the bridge apart tomorrow and see what I can do to make it DCC friendly, and maybe replace the motor with a 5 pole.
     
  6. rray

    rray Staff Member

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    I just discovered that you can connect this turntable directly to a Digikeijs DR5052 DigiTurn DCC Turntable Controller, no modifications required:



     
  7. SJ Z-man

    SJ Z-man TrainBoard Member

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    Rob, any of the hundreds of $5 voltage/current control boards on Amazon would solve the WATTs and volts.
    Andrew on Zscale @groups io had a transfer table with some wear and tear plus oxidation in the controller that kept several of us scratching our heads.
     

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