I doubt you can get the C80 to display the output of two transducers and differentiate them. You might ask that question on the
Raymarine forum. Obviously you could have a second dedicated
transducer and display not on the same
SeaTalk network as the C80. The C80 will display the
depth from your existing
transducer and the dedicated display will show the depth from the other transducer. Possibly a switch could be used to switch between the two transducers such that the C80 could display one or the other: however, that might cause problems for the
SeaTalk network. The Raymarine Forum is probably the best source for info of that kind.
John