... 3.Tone generation, 270HZ,330HZ, Adjustable Light Source Testing Instrument Features Multi wavelength outputl Adjustable outputl power Tone generation, 270HZ ... Step(dBm)<0.5Adjustable Range≥5Stability(dB,30min,20°C)0.15Modulation(Hz)CW, 270,330,1K,2KFiber PortFC ... 4Battery Operating time(h)45 without backlightOperation Temperature(°C)-10~+60Storage Temperature(°C)-25~+70Dimension(mm)175*90*44.5Weight (g ...