MED posted:I agree with some of the posts above that, having eliminated the transformers as the source, its probably the brushes arcing, especially as they make/break two adjacent armature contact plates. More load on the engine increases the current the motor draws, thus increasing the strength of the signal emitted from the arcing.
So one attempt to isolate the problem is the motor would be to remove the body of an engine, use tinfoil to encase the motor, making sure to connect the tinfoil to track ground. This would create a shield, that would lower the emissions getting from the motor to you.
My little knowledge of motors (that can quickly get me into trouble) is that if the source is the brushes arcing, using DC or switching to DC motors (which today in our trains still have brushes) may not help very much. Now, as I have seen wished for in other posts in other topics, if DC brushless motors were available for our trains, the would have the best chance of getting rid of the emitted noise.
In my world of automotive, certain signal communication wires that are subject to this kind of interference, are wrapped in mesh backed foil.....leaving one of these harnesses exposed will set off all kinds of wonderful issues....these are sensitive reference wires that can not not be contaminated ....if you look in an auto parts store, they sell a very similar sleeve to use on spark plug wire boots to keep them from getting burnt up on headers and what not....perhaps yo might experiment with shielding the motors inside the shell???.....just don’t completely wrap the motor or it might have the adverse affect and cook your motors .......jus a thought, and my .02 cents....unfortunately that’s all I got, now I’m broke!..........Pat
