SuperKEKb X-Ray Monitor new detector breakout board revB reduces leakage paths (confirmed) access to measure more nodes with hp4156b semiconductor parameter analyzer using hp4156b to drive laser diode (thorlabs L980P010) and measure built-in photodiode photodiode appears to have linear relationship to optical power, as measured by thorlabs S121B+PM100+hp4156b plan to run at 24.5 mA 2019-01-28 XRM 2018 progress

SuperKEKb X-Ray Monitor first light! (on bench) new laser driver board (revD) drives cathode of laser directly from output of LVPECL comparator drives anode from low output impedance buffer better optical coupling into fiber and onto detector partly from 3d printed 30mm cage mounts partly from using 400um core fiber cable assemblies partly from 3d printed fiber ferrule mounted in micro-translation stage faraday cage for slac detector assembly signal goes through 40dB mini-circuits amplifiers, then into scope in averaging mode works down to 10 V bias (signal level is lower) first light! 3 adjacent channels laser driver revD fiber coupling to translation stage 2019-01-28 XRM 2018 progress

SuperKEKb X-Ray Monitor amplifier selection: carefully planning preamplifier+gain stages calculation/simulation (noise/gain/recovery time) prototyping/measurement (network analyzer) firmware/readout: modified BelleII/TOP firmware (common ancestor to previous XRM firmware) to (re)support gigabit ethernet register read/write interface - working streaming data out - working trigger input (selectable prescaling) - in progress retains compatibility with BelleII/TOP firmware and readout software (as much as possible) upcoming: next test is with SLAC strip detector and boardstack mated 2019-01-28 XRM 2018 progress