... has 4 E1 interfaces (BNC, 75OHM), 1+1 optical interfaces (FC), single mode, double core, and 4 ... , busy tone, and ring signal.Uplink port: Optical transmission distance is more than 30KM without repeat. ... 048Mbps (50ppm)l Impedance: 75Ω or 120Ωl Line Code: HDB3, compliance with ITU-T G.703l Jitter ... Port number: 4, optionall Speed: 10/100Mbps line speedl Duplex: Half duplex/Full duplex self adaptationl ...