FC/PC FC/UPC FC/APC SC/PC SC/UPC SC/APC ST/PC ST/UPC SC/

Fiber optic connectors to connect the head and the type of connection the FC, SC, the ST
Face contact with the way the PC, UPC, APC type, different sections of exposure affect the return loss of the joint
PC, UPC, APC> 40,50,60 dB
As for the one side were used and in what situations I do not know, it seems that the device on the sc and st more odf fc

FC / PC, FC / UPC the FC / APC hybrid connectors, signal attenuation will not be great, is less than 0.5dB insertion loss in accordance with the GB. Application depends on the type of adapter, general communications ODF frame FC device optical port with SC, ST in LAN and radio and television more.
PC - pin body end face of the physical end; UPC - pin body end for the super-physical end; APC type - pin body face angle of the physical end; the difference between the return loss, respectively, as follows: PC ≥ 40dB, UPC ≥ 50dB , the APC ≥ 60dB.
 
Three common fiber optic connectors:
FC / PC: FC, round pigtail connector, the PC, ceramic cross-section plane;
SC / PC: SC, square head pigtail connector, the PC, ibid;
FC / APC: FC, ibid, APC, the cross-section center as the center, outward tilt of 8 degrees.