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The Kaos spectrometer is maintained by the A1 collaboration at the Mainz Microtron MAMI with a focus on the study of (e,e^\primeK^+) coincidence reactions. For its electron-arm two vertical planes of fiber arrays, each comprising approximately 10000 fibers, are operated close to zero degree scattering angle and in close proximity to the electron beam. A nearly dead-time free DAQ system to acquire timing and tracking information has been installed for this spectrometer arm. The signals of 144 multianode photomultipliers are collected by 96-channel front-end boards, digitized by double-threshold discriminators and the signal time is picked up by state-of-the-art F1 time-to-digital converter chips. In order to minimize background rates a sophisticated trigger logic was implemented in newly developed Vuprom modules. The trigger performs noise suppression, signal cluster finding, particle tracking and coincidence timing and can be expanded for kinematical matching (e^\primeK^+) coincidences. The full system was designed to process more than 4000 read-out channels and to cope with the high electron flux in the spectrometer and the high count rate requirement of the detectors. It was successfully in-beam tested at MAMI in 2009. [ABSTRACT FROM PUBLISHER]

A new front-end electronics system has been developed for the electron arm tracking detectors in the KAOs spectrometer at the Mainz microtron MAMI. The signals of multi-anode photomultipliers are collected by 96-channel front-end boards, digitized by double-threshold discriminators and the signal time is picked up by F1 TDC chips. The system was designed to process more than 4,000 channels and to cope with the high electron flux in the spectrometer and the high count rate requirement of the detectors. A subset of 288 channels was installed and successfully used in the 2008 data taking period of the KAOs spectrometer. [ABSTRACT FROM AUTHOR]