How exactly do you wire LED ditch lights onto a DCC decoder’s function, so that the lights alternate while flashing? What if it’s a double sided locomotive like the Acela HHP-8 what functions would you use for ditchlights, and one or two LED bulbs per fuction?
One bulb per function. For the HHP-8, you MAY use the decoder’s 6 outputs like this:
F0F= Front Headlight
F0R= Rear Headlight
F1= Front L or R Ditch
F2= Front R or L Ditch
F3= Rear L or R Ditch
F4= Rear R or L Ditch
Of course, this means that you have Red-Rear lights or internal lights (requires more functions).
Each LED will need the proper resistor.
Each LED will need to be programmed (depending on the decoder).
Not all decoders will handle LEDs properly. Digitrax Decoders dont like LEDs that much (the variance in the output to the LED is not really enough to simulate a flashing ditchlight). Other MFGs of decoder will give you better lighting effects with LEDs.
Beyond this help, I suggest you either do a search on these forums or a Google search. This topic has been brought up many times.
David B