Check the listing for details. Optical Talk Sets Light Source All-in-one Machine For Underground Construction. Condition: New. Listed at 629.00 USD. Optical Talk Sets Light Source All-in-one Machine For Underground Construction Note:Batteries not included in shipping！！！ Product Description This is a practical instrument that uses actual line optical cables for communication in the process of optical network construction, testing, emergency repair, and maintenance, when communication is inconvenient or under harsh conditions. When constructing in caves or underground areas, communication links can be quickly established for high-quality, long-distance, and full duplex communication. This product also provides stable light source power and can be used in conjunction with an optical power meter for fiber attenuation and loss measurement. Specification Type Wavelength(nm)1310/1550Emitter TypeFP-LDTransmission Distance(KM)≥100Dynamic Range(dB)≥ 33Output Power(dB)-5~-7 Modulation(Hz)CW,270,1K,2KOutput Stability (dB,30min,20 °C )≤ 0.1Power Supply3 pcs 1.5V Alkaline Batteries/8.4V Power Supply AdaptorBattery Operating Time5 hoursOptical ConnectorFC/PCOperating Temperature(°C)-10 ~ +60Storage Temperature(°C)-25 ~ +70Dimension29*23*8.5cmWeight3.5kgRemark: We also provides Fiber Optic Clipon Coupler device according to customers needs Features Full duplex digital communication with high quality conversation connection & low background noiseTogether with Optical Clip-on Coupler, enables on line communications availableCombining functions of both a digital optical phone call and a stabilized light source.Large LCD display with backlightLow battery power indication