QSI Revolution / Magnum

For the Large Scale product, the correct name for this decoder is the "QSI Revolution", but there was a lot of confused marketing, where people saw the board packaged with a screw terminal board, and the board or board and decoder marketed as the "Magnum". Even QSI changed the name in various manuals.

In any case there is only one version of the main board hardware. The variations were that sometimes certain pins were cut off that caused issues with Bachmann locos (Bachmann not following the "Aristo socket" standard.) and if it was sold with the adapter board, that has screw terminals for the pins on one end.

qsi decoderqsi magnum


There are a ton of connectors on this board and some are tiny! Do NOT pull the connectors out by the wires!!! Most fit tightly and you will rip the wires OUT of the connector!

Also note well: all the connectors are DIFFERENT, so be careful where you are plugging what.

Wiring Diagrams and pictures:

Here's a picture of the board labeling the connections:

qsi revolution pic


upper right 2 pin connector, this is the speaker output, says "SPKR"

next down on the right edge, 3 pin connector, chuff switch, note only 2 of the 3 pins used, says "CAM" (chuff cam)

next down a bit off the right edge, the 5 pin connector for the flat flex cable to the optional Airwire receiver, says "RADIO"

bottom right corner, 2 pin connector for reed switch, used to do some programming manually and reset, says "REED"

to the left of the reed switch, the larger white 3 pin connector is for a never-produced lighting board that was to have more outputs, says "LTG" (lighting)


Below diagram of the board with connections. NOTE! The connections shown on the "magnum" socket board are WRONG. Read the silkscreened letters by the screw terminals. The headlight (FL) and the backup light (RL) are reversed from the picture below.




More on connectors;

Reminder: all the connectors are different.

P9 - 2 pin speaker connector - can get spares from All Electronics, part SBC-1

P2 - 3 pin chuff switch connector - only pins 1 & 2 are used. Only came with decoders ordered as steam version

P5 - 5 pin flat cable, comes with the Airwire receiver. NOTE: the cable only has contacts on one side, likewise the sockets on the AirWire receiver and the QSI board have contacts on one side. The is far and away the most common issue people have when connecting this. Use a magnifying lens to be sure on the sockets.

P3 - you can't use this, so never looked into it, they were going to market an add-on device with more light ports.

P1 - small 2 pin connector for the reed switch - you get a reed switch with every decoder, I never use them


Other Revolution products:

There were HO units also.




The Revolution only accepts Q2 sound files, and not to be confused with the Titan Q2FX,  files. (Q3 files are exclusively ET - Emulator Technology).


  Revolution / Magnum Sound files       
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