Ultra-low-charge operation of free-electron lasers down to 1 pC or even lower, requires adequate diagnostics for both, the users and the operators. For the electro-optical bunch-arrival time monitor (BAM) a fundamental design update is necessary to yield single-digit fs precision with such low charges. In 2023 a vacuum sealed demonstrator for a novel pickup structure with integrated combination network on a printed circuit board (PCB) was built for operation at the free-electron laser ELBE at HZDR. Together with a new low-pi-voltage ultra-wideband traveling wave electro-optical modulator, this concept reaches an estimated theoretical jitter charge product of 9 fs pC. Proof-of-concept measurements with the pickup demonstrator were carried out at ELBE.

The ELBE radiation source at HZDR has a long success story of delivering bright and powerful infrared and THz beams to a broad user community. Following the science driven user requests we have written a conceptual design report for the Dresden Advanced Light Infrastructure (DALI) as a successor to ELBE. The proposed DALI facility aims to increase the spectral brightness and pulse energy by orders of magnitude while providing two decades of tunability over the whole THz spectrum. It utilizes different radiation production schemes adapted to the wavelength range - super-radiant undulator sources for the long-wavelength THz range and an optical klystron driven by an oscillator FEL for the far-IR range. All sources are driven by superconducting linear accelerators allowing CW operation. The facility layout is chosen such that parallel operation of all sources is possible and great versatility is available to provide users with pulse repetition rates from single-shot to 1 MHz with flexible timing and the ability to combine sources. A positron source and a UED setup are planned to complete the facility.

The CW electron accelerator ELBE is in operation for more than two decades. The timing system has been patched several times in order to meet changing requirements. In 2019 the development of a new timing system based on Micro Research Finland Hardware has been started which is designed to unify the heterogeneous structure and to replace obsolete components. In spring 2024 the system has been put in user operation. The contribution will discuss the commissioning process and first experiences from the routine operation.

Ultra-low-charge operation of free-electron lasers down to 1 pC or even lower, requires adequate diagnostics for both, the users and the operators. For the electro-optical bunch-arrival time monitor (BAM) a fundamental design update is necessary to yield single-digit fs precision with such low charges. In 2023 a vacuum sealed demonstrator for a novel pickup structure with integrated combination network on a printed circuit board (PCB) was built for operation at the free-electron laser ELBE at HZDR. Together with a new low-pi-voltage ultra-wideband traveling wave electro-optical modulator, this concept reaches an estimated theoretical jitter charge product of 9 fs pC. Proof-of-concept measurements with the pickup demonstrator were carried out at ELBE.