100 to 200 GHz interleaver for C-band. With 3 LC/PC connectors. Removed from Lucent 40-ch DWDM C-band systems (see last 4 photos below). The frequency (wavelength) grid numbers are printed on the front of the DWDM system, 9200 means 192.00 THz frequency (1561.42nm). In this DWDM system, input 100GHz spaced signals pass through the interleaver firstly, one output is 200GHz-spaced odd-channel signal, the other output is 200GHz-spaced even-channel signals. The even-channel signals pass through 1x20 200GHz demux at our Store Part No.: FFC-MUX-017C . This interleaver is sometimes called de-interleaver. It may also works with mux, but it depends on your requirement. With model number but no datasheet or test sheet due to discontinued products. This P/N: FS100-LT2A performance would be similar to  test data for P/N: FS100

Tested OK with our temperature controller in our lab, but we were too busy to record the results at that time. Tested locking at ITU grid with temperature controller. We verified that Pin3: RTDB1 and Pin4: RTDB2 are internally connected. Pinout info is verified same as the 1st pdf link below, and also 2nd pdf link below for almost same P/N: FS100. Basically you need connect two heater pins and two RTD temperature-sensor pins to your temperature controller (many types of temperature controllers support RTD temperature sensor). Then you can easily set interleaver to required temperature (70.8 C).

Since the temperature controller by wavelength electronics was sold, we simply tested the interleaver sample again without TEC. See our test results at the zip link below (wavelength and power is not calibrated). The insertion loss is low (We guess 0.7dB including one connector loss). Since the connector may not be cleaned well, so this is only approximate estimate.