Will the 8 pin plug on an N scale decoder fit the 8 pin receptical on an HO board? In otherwords, are they the same size?
If so, what are the limitations, if any, on using N scale decoders in tight fit HO applications?
The NMRA 8 pin plus if the NMRA 8 pin plug, regardless of the decoder it is attached to. “Scale” for decoders refers mostly to the physical size of the decoder. Sometimes the smaller decoders have a lower maximum current, this is the only thing to check before using a decoder listed as “N scale” in an HO loco. There’s no other downside other than the smalelr N scale decoders usually cost more for what’s otherwise the same decoder - same number of functions, etc. It costs more to make thing smaller. If you have the N scale one laying around, fine, but I wouldn;t purchase an N scale decoder when the larger one will fit.
–Randy
Just in case you get a loco with no indication of pin 1, the orange wire on the plug is pin 1. If you inadvertently plug in incorrectly, no damage. The loco will just run in reverse of the selected DCC controller direction and the front and rear lights will be reversed. Some new users have done this. The NMRA did this intentionally.
About eight years ago I installed some N scale Lenz decoders in HO scale tender drive locos with low current requirements. No problem. I took them to my local club to demonstrate DCC using an old MRC 2000 DCC controller. A couple years later they went to DCC with a NCE Power Pro. Never looked back.
Make sure you measure loco current with a multimeter and a DC power pack.
Rich
If you have an HO loco with really tight space you can always hardwire in a Digitrax DZ125 decoder, or splice it to an 8 pin socket so it can be plugged in. The DZ125 is sized for Z Scale but is robust enough for most HO equipment. I have a couple in a pair of SDP40F’s that can pull a heavy train all day long without turning a hair. Only problem is it’s a 2 function decoder. Motor and light control. It is Soundbug compatible and has BEMF.
Thanks, Running Bear. Since I’m limited to first generation diesels is there anything I’m giving up if I use 2 function decoders? I won’t need ditch lights for sure, but is there anything I’m missing?
Nope. If you’re modelling first generation diesels when they were new, and you aren;t doign Southern Pacific, you should be fine with a 2-function decoder. Unless you have a Geep that also had a Mars light, then you’d need 3 or 4 functions, 4 if they had the Mars light on both ends. My railraod had none of those things, just simpel headlights, so I use 2 function decoders for just about everything, and usually hard wire them in which allows for more room by removign the facroty board. I also repalce bulbs with golden white LEDs using 1K resistors for burnout-proof lighting.
–Randy
You can program a mars light function on the DZ125 but you can’t have the headlight and mars light both unless you put both the front and rear lights at the front of the loco. One can be programmed to be a regular headlight and the other can be a mars light that can be on during forward running and off in reverse or on all the time. It’s all in how it’s programmed.
That works for E’s and F’s that don’t have a rear light [:D]
If you have a Geep that has front and rear lights as well as Mars lights at both ends you’ll need 4, unless you don;t mind the rear lights being on at the same time as the front ones.
–Randy