Bob,
FYI, I would buy a TCS decoder if you haven't bought another one yet. To me, it's the best non sound decoder by far.
Richard
I purchased the two locos (P2K FA2's) together, but used, on Ebay about a year ago. I installed the DZ123 a few days ago after removing a NCE D13SR decoder because it wouldn't fit inside the body (without removing the fan drive, as was suggested on another thread). I have since thought about removing the fan drive and using the NCE decoders on both locos, if they would be a better choice. I haven't ordered another DZ123 yet, awaiting an educated decision based on what recommendations I get from you guys that have consisting experience. The DZ123 seems to work fine on the stand alone install, lights work (LED replacement) as they should and speed is very good at slow speed. I do have and use JMRI DecoderPro for all my programming. I will do a speed match by running both locos to see which needs adjusting, until they both run at approximately the same speed.
-Bob
Life is what happens while you are making other plans!
I have found that Digitrax decoders have an annoying quirk. When they are in a consist, the BEMF is turned off. Yes it can be corrected by a CV setting, but it's annoying that Digitrax did this in the first place. That means that when you consist a Digitrax decoder with another decoder, the Digitrax unit will be almost half as slow as the other unit because no other decoder manufacturer turns the BEMF off when in a consist.
So in your case, I would advise you to get another Digitrax decoder for the other locomotive. Then they will both run half as slow, but at least they will be at the same speed.
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.
The entire concept of consisting and speed matching with different brands of decoders is why the NMRA DCC Standards and Recommended Practices came up with all the CVs required to do this.
Matching the speed steps is more important than matching the decoders. If you have JMRI, then speed matching is relatively easy for different decoders. Just need a timer and specified length of track. Or you can have one chase the other and dial them in so they don't hit or run away from one another. I use a timed 6' length of track and set speed points and limits. I mix TCS, Digitrax, Soundtraxx, etc.
My feeling is that it makes good sense to use the same decoder in each loco that you are consisting.
That said, if the locos are purchased separately at different times, that raises other issues. Did the original decoder fit nicely, is it still available, and does it provide all of the functions that you consider necessary or desirable?
In the case of the DZ123, it is still available, but it is an economy 2 function decoder. The more expensive decoder with 4 functions is the "matching" DZ143.
Rich
Alton Junction
Some decoders from other manufacturers do not support all of the CV's used when speedmatching, so it may be best to use the same decoder from the same manufacturer in both loco's.
I have two FA2 diesel locomotives that I am going to consist or run together all the time. Is it better to use the same brand/model decoder in both engines or does it make any difference? I have a Digitrax DZ123 in one loco and am getting ready to convert the second one to DCC.