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New Member
Many years past there was an article in Model Railroader Magazine with the schematic diagram of the CDU. Does anyone have that schematic . I made one and now I need to repair it, but I don't have the schematic.


Well-Known Member
there are a couple of different types, just a cap, resistor, and [maybe] a diode ... to ones that have a transistor, or two, or three on the final pass end ??
what is yours?


Well-Known Member
the -most- common is for the transistor to go bad ... do you have a transistor tester, or failing that, a replacement transistor ?
the diodes and resistor can be checked out of circuit with a multimeter

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