Motorola R1225 Question

Just got one of these repeaters to replace my downed gmrs GE.



The radio portion of it (not the control head ) has an antenna port on the back ( near the power) and one in the front. Anyone know which is Tx and RX?



Also, sans a duplexer, how far apart do the antennas need to be??



Thanks.

Motorola R1225 Question