new engineer has some questions

[peterb]

New to the hobby, started with my old Burlington switcher and a few old cars, and it seems to be getting bigger from there.
I would appreciate some help on a couple things:
1.  Will any DCC locomotive run on a DC layout?  Specifically a Spectrum? 
2.  Want a steam locomotive someday.  My layout has both 22" and 18" curves, but no 15".  What size limitations do I have so as to avoid derailments and any other operating troubles?

[SteamGene]

Spectrum locos with Bachmann decoders will work on DC.  So will BLI.  Others I'm not sure about.  I believe Tsunami will work on DC, but I'm not sure about other Soundtraxx decoders. 
For appearance sake, the largest steam with 18" radii should be no larger than a 2-8-2.  There are many which are made to negotiate 18" (the Rivarossi 2-6-6-6 C&O H-8 being one example), but they look awful there.  For Bachmann, I'd suggest the 4-4-0, 4-6-0, 2-8-0, 2-10-0, the Chinese 2-8-2 if you can find it.   In IHC, I'd go for a NEW 2-8-0, 2-8-2, or 4-6-2.   Model Power Mantua, the 2-8-2 or the 4-6-2.  BLI, the USRA light 2-8-2. 
Gene

[Yampa Bob]

Good advice.

Welcome to the hobby Peter.

Bob

[RAM]

If you have a DC layout and it is going to be a long time before going to DCC, then why pay for a decoder that  you will not be using.  As long as the locomotive is DCC ready, than you can always add a decoder.

[peterb]

Been away for awhile, but thanks for the advise, SteamGene, on the locomotives.  I have been buying a few locomotives, DCC plug w/o decoder.
Thanks Again.

[SteamGene]

Welcome back. 
Gene