DHODT-16 16E1 Optical Multiplexer refers to design of highly integrated structure and provides 16 standard E1 interfaces together with one channel of order wire, with self-contained alarm and NM functions,as well as self-testing and E1 loop-back testing functions.Alarm signals are provided in a full range,including LOS,LOF,10-3 error code,and 10-6 error code alarms of line side as well as LOS  and HDB3 coding violation alarms of E1 bypass,and available with sound alarming signals.it has become a steady and reliable NG transmission product,nice in appearance and delicate,economical and practical,with good transmission performance.Transmission impedance can be matched through simple contact pin and patch cord or DIP switch setting,and at the same time different adapters can be selected to adapt to different interfaces.The product can be applied to construct economical and flexible multi-service transmission networks,used for relay between switch offices,data transmission of LAN