We describe the perofrmance of a low-loss couplerless bi-directional transmission experiment which operates at a single wavelength. The system is unique in that it employs an annular In
0.53Ga
0.47As/InP photodetector and has potential for use for both long-wavelength (

m) and short-wavelength (

m) transmission. We find that the optical crosstalk between the near-end transmitter and receiver is as low as -16.6 dB (-33.2 dB electrical) for a 200-m link: a value acceptable for use in many short haul system applications.