What should one use to program an older QSI Quantum decoder? As I run MRC the QSI decoder won't program on the program track, only on the main...The decoder I am running requires programming as its consisted with another loco that just has a standard Digitrax Decoder .The digitrax decoder is easier to reprogram and I have changed many settings on it to try and consist the two but the QSI is fighting the digitrax especially at startup...
Many sound decoders, especially the older ones, don't work well with the standard programming track signals.
For QSI decoders a programming track booster is recommended. I cannot tell you if that will work with an MRC system. Another solution is the Digitrax PR3/PR4, which connects between a program track and your computer, which can program the CVs.
https://dccwiki.com/Programming_Track#Programming_Track_Boosters
You will need software such as JMRI on your computer if you go the PR3/PR4 route.