The neutron capture cross-section of 234U has been measured for energies from thermal up to the keV region in the neutron time-of-flight facility n TOF, based on a spallation source located at CERN. A 4π BaF2 array composed of 40 crystals, placed at a distance of 184.9 m from the neutron source, was employed as a total absorption calorimeter (TAC) for detection of the prompt γ-ray cascade from capture events in the sample. This text describes the experimental setup, all necessary steps followed during the data analysis procedure. Results are presented in the form of R-matrix resonance parameters from fits with the SAMMY code and compared to the evaluated data of ENDF in the relevant energy region, indicating the good performance of the n TOF facility and the TAC.