Merry Christmas Mr. ABC and many thanks for your reply. It is helpful, informative and greatly appreciated. I shall surf the web looking for the MTH and BLI units you have mentioned. I have seen some DCC steam engines with smoke, sound, etc. Would these functions work work with our dc MRC 220 or would  a DCC controller be required to operare these DCC equipped trains? I also plan to start reading up on these things very shortly in hopes of gaining a bit more knowledge. Again thank you for the reply.
Gods' Blessings to you and yours,
Frank aka "Bigfingers"

Howdy and Merry Christmas. We (wife aka "BOSS") and I have Christmas Village goes up once a year. Always  clean every piece of silver track before putting into operation and as taking down after holidays. This year the smoke unit doesn't function. Have tried carefully to clean the unit with no success on smoke generation. Engine runs fine and pulls 3 -7 Spectrum heavyweight passenger cars with no problems. Smoke is a big thing for us.
If the engine doesn't smoke then it doesn't give friends, family or us the enjoyment we expect. Yes, wrote a book, sorry for that. Any ideas on getting the smoke unit working would be greatly appreciated by this "rookie" HO train operator and his wife ("BOSS").
Smiles, Gods' Blessings,
Frank aka "BIGFINGERS"