The NK2800 mini optical time domain reflectometer is compact and easy to carry; it adopts a 3.5-inch high-definition touch screen, supports multi-touch and smooth operation. Internal integration of OTDR, event map, optical power meter, red light, flashlight and other functions in one, to meet various test needs in different occasions. Among them, the OTDR func- tion adopts 1550nm wavelength and built-in high-efficiency wavelength isolator. It can perform optical test on 1490nm and 1577nm links. It supports up to about +10dBm with optical test capability, and the maximum measurement range is 80km.