We present design criteria for minimising the influence of f2 noise in broadband heterodyne optical receivers using a serial or parallel tuning inductor. The criteria are tested experimentally in a 2GHz-bandwidth front-end design. A 4dB receiver sensitivity improvement is demonstrated for a 400 Mbit/s ASK heterodyne application, and a 1 dB/2 dB sensitivity improvement is demonstrated for a 2 Gbit/s direct-detection/homodyne application.