WT-1550-EM30 series transmitter has 7 function modules: RF control, DFB laser, optical modulator, SBS control, CSO control, communication/display control and power supply. Automatic gain control circuit (AGC) or manual gain control circuit (MGC) amplifies the RF signal. It is designed especially for second-stage service area, CNR ≥50. 50dB when tested in 59CH PAL/D, SBS set at 13dBm, point to point 50km fiber. Mounted. At the heart of every optical transceiver lie three essential components, often called the “Three Pillars” of optical communication: Laser — generates light. Modulator — encodes data onto the light. The. This article compares direct modulation and external modulation, highlighting the differences between these two optical modulation techniques. Direct and external modulation are primarily used in the optical domain with LED and Laser devices as methods for converting electrical data into optical. An optical module usually consists of an optical transmitting device (TOSA, including a laser), an optical receiving device (ROSA, including a photodetector), functional circuits,main control circuit board (PCBA), housing and optical (electrical) interface and other components. ★ Perfect SBS suppress circuit and adjustable SBS in 13~19dBm,suitable for.