Scheible, B.E.J. Ackermann, W. Czwalinna, M.K. De Gersem, H. Freitag, M. Kuntzsch, M. Nazer, T.A. Penirschke, A. Schlarb, H. Vilcins, S. JACoW Publishing Geneva, Switzerland 2673-5350 978-3-95450-236-3 10.18429/JACoW-IBIC2023-TUP012 English 214-218 pick-up electron laser free-electron-laser FEL Contribution to a conference proceedings 2023 2023-12 https://doi.org/10.18429/JACoW-IBIC2023-TUP012 https://jacow.org/ibic2023/papers/tup012.pdf A vacuum sealed prototype of an electro-optical bunch-arrival-time monitor has been commissioned in 2023. It comprises of a pickup-structure and a low-pi-voltage ultra-wideband traveling wave electro-optical modulator. The stainless-steel body of the pickup structure is partially produced by additive manufacturing and comprises four pickups as well as an integrated combination network on a printed circuit board. This novel design aims to enable single-shot bunch-arrival-time measurements for electron beams in free-electron lasers with single-digit fs precision for low bunch charges down to 1 pC. The theoretical jitter charge product has been estimated by simulation and modeling to be in the order of 9 fs pC. The new prototype is tailored for validation experiments at the ELBE accelerator beamline. In this contribution first measurement results are presented.