While a RRAmpmeter is a great tool, I find a digital multimeter much more useful.? However, you need to make sure it reads true RMS voltage and has a high enough frequency response to work with DCC signals.? What I've been using is a OWON B41T+ meter that I bought from Amazon for about $80.? Had it for several years now and it is definitely worh the price.? It gives me accurate DCC reading but does much more in working on layout and electronics in general.? Most general purpose multimeters, even Fluke, don't have the frequency response to work with DCC.? I have 4 different multimeters that I've bought over the years and the OWON is the only one that works for DCC.
Good Luck, John Moonan
