MTC21 Decoder in CMR-line locs HELP

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The middle number please? (6): 6

MTC21 Decoder in CMR-line locs HELP

Post by AsianRailFan » 10 Oct 2018, 18:24

Hi @all,
Please can any of you help me out with MTC21 decoders installed
in the CMR-line locs I purchased from
That is DF4DK#3305, SS6B#6026, SS1#016, SS1#173.
They all came with a MTC21 installed decoder, but with no DCC manual at all.
The good thing is: they ran OK out of the box, using ROCO Z21 controller.
The surprise/disappointment is: the speeds are not properly controllable.
For scale speeds, long trains, and driving in consist that is unwanted to say the least.
Let me illustrate some behaviour:
CV#5 is programmable but has no effect on (top)speed whatsoever.
CV#2,3,4, do have some effect. In CV#6 only 0,1 are allowed, else no running.
CV#19,29, are programmable and as far I can monitor do have normal effect.
Any other NMRA M/O/R cv# regarding speed, force, acceleration are either not programmable, or have no effect.

I for trial installed ZIMO and TAMS decoders in the optional 8-pin NEM652 sockets, they work great, so it is not a CMR-line issue, but a decoder issue.
CV#8/7 reads 165/3 that points to a MERG decoder, but digging and mailing MERG's website had no answer/result.
I contacted Hobbyking, they after long correspondence referred to NMRA standards (that obviously do not work).
I can not read/write Chinese so contacting CMR-line is not possible for me.
It also remains the question whether CMR-line or HobbyKing installed the decoders.
They look very sophisticated, no junk, so there should be some operation manual somewhere.

Can anyone help me on this issue?? I do want to use the installed decoders if possible.

Cheers, Jaap

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