By using the linear electro‐optic effect in CdTe to mix a 10.6‐&mgr;m laser output with a pulsed (1–4‐&mgr;sec duration) microwave field produced by a magnetron, the laser’s output was shifted by 16 GHz with ≈ 27% conversion efficiency. By mechanically adjusting the microwave structure containing the CdTe and using a frequency‐swept microwave source, the shift was demonstrated to be tunable from 13.9 to 17.0 GHz.