American Models RS-3 TMCC Conversion
Using ERR's new Mini Commander2 and Railsounds Commander

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The American Models RS-3 has a very narrow hood. This makes a TMCC install a challenge. The new Electric Railroad's Mini Commander 2 and Railsounds commander will fit with some minor modifications to the loco. 
The room for the speaker is tight. I mounted 4 micro speakers in the roof of the shell.

One speaker is mounted at each end of the shell

Two speakers are mounted in the roof above the motor. The speakers are wired in series pairs and then pairs are paralleled so the impedance remains at 8 ohms. 

The flywheel was removed and chassis weight boss was milled off to make a place for the program/run switch hole. 

The Mini Commander2 bracket has a notch cut out for clearance for the boards output transistors cooling 



Mounting brackets for the boards are made from .015" brass stock and screwed to the frame.
Notice that the drive shaft universal joint has been beveled for the sound board's capacitor clearance.

The Motor was temporarily removed to mill 1/16" from the motor mounting pad end. Then the motor was reinstalled moved forward 1/16" for the sound board clearance.   It was also rotated about 90 degrees for the motor terminal clearances

The Mini Commander2 components straddle the drive shaft.  

Notice the lighting Molex connector glued to the frame support. this makes the shell removal easier. 

The sound board's capacitor just clears the drive shaft U-joint after the joint is beveled. the sound board is mounted flush against the motor to clear the power truck.  It is a close fit but it does work. The speaker's Molex connector is mounted to the frame support also.

YouTube video of the RS-3 conversion