In case of a need for a second return path optical transmitter in the node or for an extra service in the module the rebuilding of the original circuit is not enough, a new module must be developed. Such a module is the ROT-HLW1-PG for Harmonic HLN-3830 and Antech LLRX200 types. The module has an extra feature mentioned above, the switchable pilot generator. This generates a reference signal allowing to grade the optical section of a HFC network independently from the coaxial section. This is very useful in cases, where the two sections are maintained by two different teams.