A prototype device capable of splitting an x-ray pulse into two adjustable fractions, delaying one of them with the aim to perform x-ray photon correlation spectroscopy and pump–probe type studies, was designed, manufactured, and tested. The device utilizes eight perfect silicon crystals in vertical 90° scattering geometry. Its performance has been verified with $8.39\mathrm{keV}$ synchrotron radiation. The measured throughput of the device with a Si(333) premonochromator at $8.39\mathrm{keV}$ under ambient conditions is 0.6%. Time delays up to $2.62\mathrm{ns}$ have been achieved, detected with a time resolution of $16.7\mathrm{ps}$ .