There is no NMRA standard or specification for RF interference or any circuitry for the supression of such interference. The loco works fine on the recommended straight DC voltage, so it's compliant. But the capacitors paralleled with the motor WILL interfere with a decoder's high frequency drive.
Don;t read too much into NMRA 'compatibility'. There is no standard for DCC installations, there is no standard as to what is meant by "DCC Ready". The DCC standards and RPs apply to the signal ont he track and how the decoders need to respond to them. They do not in any way cover the wiring of said decoder to the locmotive, other than to define a couple of standard plug and socket arrangements and the colors of the wires. There is no corresponding standard for the color of the wires in a DC loco. Some makers use the DCC colors so hard wiring is simply a matter of matchign the color on the decoder with the color on the loco, but others use all black wires. For DC, if the loco moves forward when the right-hand rail (facing the same direction as the loco) is positive and the motor is designed to work on 12 volts DC, it's compliant.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I recall reading something about that in the loco's instructions. But scince the Tsunami is NMRA compatible, there should'nt be a problem, should there?
Based on previous experiences here, for best operation it would probably be best to remove the Bachmann circuit board. However, each different loco seems to have a different board so perhaps the one in the Connie is ok. The main issue is with the rf supression caps and chokes Bachmann ses - they interfere with the high frequency drive and BEMF of good quality decoders. Sheldon is the resident Bachmann steam loco expert - and his experiences with the control of the locos is applicable to DCC because his control system uses the same sort of high frequency PWM control. Straight DC is usually ok, as are Bachmann's cheap DCC On Board decoders because they don't have the high frequency 'silent' drive, nor do they have BEMF.
If you're going to retain the Bachmann printed circuit board that is in the tender, you do not need a resistor for the headlight. If you remove the Bachmann board, which you will probably have to do to fit a Tsunami into the tender, then you will need a 1K Ohm resistor in the headlight lead.
I plan on soon putting sound in my Bachmann Spectrum DCC Equipped 2-8-0 Consolidation, any tips on making sure that the installation goes well? Also, scince i can wire a sound decoder directly to the old plug, do i need to put in a resistor to protect the LED headlight? Or is the voltage automatically lowered by the PC board already inside? I plan on putting in a "Soundtraxx Tsunami Medium Steam" sound decoder. I'm aware that "light steam" would be more true to the prototype, but the sound of Medium steam seems a bit more like music to my ears .
Anyways, thanks for any help!