A PNP transistor is driving the filter as Tx, just before the 47nF cap. After the transmission line there is another filter which have the same values. When I look the received signal with a scope I see the ringing. I also try to change the receiver part to be sure that the Tx is making the ringing, nothing changed so I doubbed the conclution.
53kHz bandwith is strange, which program are you using? I am triying to learn "filter solutions". After giving the values I changed some values in order to standardize them. Maybe I am doing something wrong?