I purchased a Bachmann HO set (Santa Specials I think) and addition track to expand.  I have a left and right remote turnout. Is there a way to make this alternate automtically so that the train takes a different route each time around ? If so what do I need to accomplish this ?  The expansion simply adds another radius to one end of the the default oval track layout. So I basically want the train to take the inside radius on one pass then outside on next and to continue that pattern.

Would like to get this going today so we can set up around tree.