About -6dBm/channel. With 1.3um and 1.55um test result at last 2 photos from manufacturer or previous user.

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1310 nm & 1550 nm  Multi Channel Laser Diode Source with Drive Electronics

This item contains two laser sources with a peak wavelengths of 1310.94nm and 1549.56 nm. Please refer to the photos to see output spectrums.  It has drive circuitry that controls and stabilizes the output power level.  Each laser output is routed through an optical isolator and then a 1 X 8 splitter and to bulkhead mounted connectors.  1310 nm output is on the left side of the unit and 1550 nm connectors are on the right side.  Please refer to the pictures to clarify the explanation.  All connections between components are connectorized.  When this was used the output power level at each of the 16 connectors was adjusted to about -6 dBm.  

This source was used by an optical component manufacturer to supply steady state constant power in an optical component assembly area.   

We have tested output of each channel in our lab. They are between -6.0 to -8.0dBm. Only one 1550nm channel has almost no light.