DW-OT55EM is an international general technical standard of high-grade type external modulation optical transmitter, used mainly for TV image signal, the digital signal and the data signal of the long distance optical fiber transmission. This product is light path part adopt international famous brand 1550nmDFB laser and high performance LINbo3 modulator, system optimization control. 47 ~ 862MHz broadband, CNR = 53dB, CTB = 65dB, CSO = 65dB, SBS: 13, 16, 18 adjustable, can meet the high quality of CATV network transmission of video, audio data. The machine is equipped with perfect RS232 communication interface, an optional SNMP network management software and 1+1 power supply backup, chassis temperature can achieve the automatic control.