The D-15-FC is a 29 GHz detector designed for 400–1700 nm measurement applications where an instrument-style product is desirable. The D-15 provides a peak responsivity of 0.2 A/W at 850 nm with an ultrafast impulse response of 15 ps. The internal Clean-pulseTM design assures low group-delay response necessary for time-domain, digital applications. This instrument provides a high performance MSM detector in a hand-held, rugged, black-anodized case. The case contains the detector module, power conditioning circuitry, photocurrent monitor, fiber optic input port, and Anritsu K output connector in addition to a power switch and battery indicator light. Designed with R&D applications in mind, it can be attached to virtually any diagnostic instrument to provide optical capability.