I plan to fit DCC/Sound to my J Class loco (Ref. # 82105). It appears to be DCC ready, with an 8-pin decoder socket (currently occupied by a blanking plug)on the circuit board in the tender, the floor of which is perforated to accept a speaker. Do I need to make any modifications to the existing lighting circuitry/components to ensure OK function of the lamps on the front of the .oco and rear of the tender, when running DCC?
All quality decoders have many lighting related CV's. You should be fine
I know that CVs can be used to set up control of loco lighting under DCC. My concern is that, when going from DCC-ready to DCC, whether its necessary to alter the original lighting circuitry to either protect/replace the original filament bulbs, because of the possible increase in the supply voltage to them.
I'm not the electrician that a lot of model railroaders are, but when you consider that DC operated engines generally run on voltage 0-12 and that for motor usage DCC rectifies to DC a track AC voltage around 13 or so, it seems reasonable to assume the original bulbs are good. If you have the knowledge and ability though, LED lighting looks a lot better, to my eye anyway.