Call me old fashioned , but ... how good is a schematic of DIRECTIONAL coupler without (I/O) pins / terminal numbers and without # of turns and without "dots" indicating winding directions ? Probably the "direct in / out " is a single turn, bout source and load . I do have some doc about number of "coupling turns", but the directions are just guess. PS I have not figured out why the first app has the K1 relay / switch. Will do some more reading on it.