Iron Planet Hobbies
NixTrainz Decoder Buddy ~ New Version 5 ~ 12 Outputs ~ For 21 Pin Decoders
This product is versatile in terms of direction of the placement of the board and mounting in various configurations.  It can easily replace a QSI board, a Dual Mode decoder board or be mounted directly on the electric motor or frame with Kapton tape.  (It is recommended that a piece of Kapton tape be placed on the bottom of the mother board to assure electrical isolation from the electric motor or frame.)
This mother board does not include the 21 Pin Decoder.
This mother board and connector board require soldering.
These printed circuit boards are NOT FOR USE IN A DC SYSTEM.
The on board resistors are sized for LEDs. (2.2K)
The mother board includes;
One 21 Pin Decoder receptacle,
Two pairs of track input pads,
One pair of motor input pads,
One pair of stay alive pads (U+ and GND),
{V5 pads for two Aux functions}
Two pairs of speaker pads wired in parallel,
Resistors for use with LED lighting. (on board 2.2K)
The connector board contains pads for eight pairs {V5 contains 12 pairs}of lighting function connections. U+ or the blue wire has eight {V5 has twelve} connected pads for the common power source. The negative (-) discrete function pads are all labeled to indicate their connection to the functions available in the decoder.
If you require incandescent lamps there are procedures that require soldering and allow for incandescent lamp use or different Decoder Buddys made specifically for the application.  Remember there are different incandescent lamp voltages and current draw that have to be taken into consideration also.
The lighting connector  was designed so that the shell of the diesel locomotive can be easily separated from the frame without un-soldering wires. This does require that the headlight and rear lights be mounted in the shell of the locomotive and that the diesel has a removable dynamic brake shell.
Decoder Buddy installed, speakers installed, decoder installed, and the motor is tested and ready.
Original vs V5
Just a few thoughts on the original Decoder Buddy and the V5 Decoder Buddy.  I try to envision your thoughts from mine.  The original Decoder Buddy does all I wanted and still does.  It has 8 matched Aux outputs for lights on a detachable small connector board, pads for a stay alive and room to solder easily.  I would very tempted to use it in locomotives that didn’t require any more than eight lighting functions.  The majority of decoders on the market at the moment have a maximum of eight  lighting outputs.  Having said that I have also considered uses for more than eight lighting outputs.  I have also considered ground lights which would be attached to the frame of the locomotive.  The V5 has 12 Aux outputs for lights.  Twelve are present on the small connector board and two are paired to the motherboard and associated with the frame.  The track and speaker pads stayed the same size.  The pads on the small connector board got a little smaller.  These pads are all separated and have holes to help hold the wires.  The stay alive pads moved to the other side of the motherboard out from under the decoder and are in an easy place to solder to like the original.  From a little closer to the situation than I used to be, I might say a Steam / Diesel split might align with the two Decoder Buddys as well as a 1997 date split between the two due to ditch light requirements by the FRA.  Both are exactly the same size.  You get to make the choice!  Fortunately both Decoder Buddys have been accepted by both installers and modelers. They are being used in models of the blue box era to the latest releases from all the major manufacturers.  Hope this helps your decision…..!
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