I understand that some decoders have an 8 pin plug. But there are also 9 pin plug ins on the motors of the engines. Will an 8 pin fit and work in a 9 pin plug? Are there many more of these mismatches? Or am I totally confused? [D)]
*Taken from the Loksound 3.5v review at Tony’s Train exchange.
No, the 8 pin plug is the NMRA “medium” plug, and arranged as 2 rows of 4, sort of like a DIP IC. The 9-pin plug is also known as a JST plug, and is 9 pins in a single linear row.
Some decoders witht he 9 pin plug come with a simple harness that has the 9-pin plug and just plain wires at the other end. In the case of the newer Athearn locos witht he 9-pin plug on them, the harness is not needed, you would remove it fromthe decoder and plug the decoder into the loco (the loco has a dummy plug installed for DC operation that you must first remove). TCS sells probably the widest variety of custom-sized harnesses witht he 9-pin plug at one end and the 8 pin at the other. These will work with any brand of decoder with the 9-pin socket on them. Digitrax sells 9-pin dummy plugs for those cases where you solder the decoder wires in palce and th eonly place it comes apart is the 9-pin plug at the decoder end. If for some reason you would wnat to remove the decoder and convert back to a pure DC loco, you would use one of these dummy plug (or keep all the ones from converted Athearn RTR and Genesis and use those - NEVER thrown anything out! Keep the excess wire when cutting the decoder harnesses to fit too, you never know when some of that thin and flexible wire will come in handy)
–Randy