1) yes I have legacy base hooked up as per Barry’s book. I have unplugged the base and totally removed it from the equation, but no difference to DCS signal.
2) yes, I have wired the 2 upper loops TIU channels to the main line and no difference in DCS signal is produced. All TIU channels are working fine. I have used GRJ’s signal checker as well on the channels.
3) I do not know what a physical obstruction would be of the elevated loops. The elevated loops run over top the lower main line only in one 8 foot section of the layout. It is my understanding that the DCS signal is propagated through the rails and not through the air as is Legacy signals.