P2K SD-7 lights????

2slim

Member
Hi guys,
I'm trying to determine how to fiddle with the lighting on a pair of HO Proto SD-7's that I want to install decoders in. What I’d like to achieve is to have the number boards lit all the time using the factory bulbs and then adding additional lights, (both my SD-7’s are SP) to be powered and controlled by the decoder. My decoder is a Digitrax DH-121 with the NMRA plug. I am aware that a 330 ohm resistor needs to be added to the stock board in order to use the factory bulbs. I'm thinking if I leave the factory bulbs hooked to the stock light board and use them for the numberboards then wire the additional lights to the decoder this will give me the effect I'm looking for. Any advice?

2slim
 

2slim

Member
Well since no one replied to this I guess I will share the results of my research. I have learned that when you are looking for decoders you want to get as many functions as possible for best price. I was somewhat unclear as to just what could be controlled with a 2 function decoder. I'll describe this with a list hopefully it will make it clear.

1 function decoder.............1 light (headlight, rear or tail light)
2 function decoder.............2 lights (1 light forward, 1 light reverse)
3 function FX decoder.........3 lights (1 light forward, 1 light reverse, 1 light FX ie: mars light, beacon)
4 function FX decoder.........4 lights (1 light forward, 1 light reverse, 2 lights FX ie: mars light, ditch lights, beacon)
5 function FX decoder.........5 lights (1 light forward, 1 light reverse, 3 lights FX ie: mars light, ditch lights, beacon)
6 function FX decoder.........6 lights (1 light forward, 1 light reverse, 4 lights FX ie: mars light, ditch lights, beacon)

OK so if you have a 1 or 2 function decoder all you can control is turning on and off lights, (the 2 function will do reverse light with direction change). If you want to make a light produce an 'effect' such as mars, gyra light or beacon. you have to dedicate a function to each light and the decoder must be a FX. I offer this discripton because I never knew this, and sought to clarify this in my own mind. I hope you find it useful.

2slim :thumb:
 
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