I am using a digitrax zephyr. How do I go about testing the voltage on this locomotive. You will have to excuse me but I am very new to this stuff. Thanks

I purchased a spectrum dash 8-40 cw dcc ready. I have not installed a decoder yet. I placed it on my dcc layout and it goes forward and then stops goes forward and then stops and keeps repeating this. I have two other non dcc spectrum locomotives that I run on this same track and they operate just fine. I placed it on a small DC track and it operates just fine. Anybody have any ideas where to begin to look for problem? Any help would be appreciated. Thanks

Just bought a new spectrum dash 8-40cw that is dcc ready. Just curious as to which decoder to install? Would appreciate any input. Thanks.