Wavelength conversion via four-wave mixing (FWM) schemes of high-bit rate data formats are conventionally achieved using a strong pump source and a secondary nonlinear device, such as highly nonlinear fibre [1] or semiconductor optical amplifier [2]. In this work we obviate the need for a secondary nonlinear device, and achieve wavelength-conversion of high repetition-rate pulse trains by externally injecting a strong optical tone directly into the cavity of the 48GHz repetition-rate passively mode-locked semiconductor laser, achieving wavelength-conversion via partially-degenerate FWM. For the first time to our knowledge, we provide experimental results of the wavelength tunability of this wavelength-conversion scheme and show that the entire signal spectrum undergoes parametrically conversion. © 2013 IEEE.