What Is Wavelength-tunable Optical Transceiver? Tunable optical transceivers are similar in operation and appearance to fixed transceivers, however, they have the added capability of allowing you to set the channel (or color) of the emitting laser. This reduces the need to have multiple devices that each operates at fixed wavelengths installed within a network. Instead, you have one transceiver that can be tuned according to the requirements of the operator. Tunable transceivers are only available in DWDM form, because of the format of the dense wavelength grid. Typical tunable optics are designed for the C-Band 50GHz. They support approximately 88 channels which are set with a 0.4nm interval. They usually start from channel 16 and go up to 61, but this is dependent on the manufacturer of the router or switch and which channels it supports. Tunable optical transceivers for DWDM systems have been widely available within the telecommunications industry for many years. ...