The XFC system was designed to record time-dependent X-ray emission from SGIII targets using an interchangeable family of snouts for measurements such as two-dimensional spatially or one-dimensional spectrally time resolved images of target features. The SGIII core XFC were designed to fit within an aluminum air-box with a large capacity cooling plane and were fitted with an array of environmental-keeping sensors. These designs of the instrument are different from earlier generations of XFC, in part, to an innovative impedance matching scheme, temporal window adjustable of 0.07~1.5 ns, advanced phosphor screens, pulsed phosphor circuits, precision assembly fixture, unique system monitoring, and complete remote computer control. The preliminary applications of advanced phosphor screens and pulsed phosphor circuits was given.