The FCAL Collaboration prepared two sensor plane prototypes for the Luminosity Calorimeter (LumiCal) and Beam Calorimeter (BeamCal) for a future linear collider detector. For both several challenges appeared. The luminosity measurement has to be done with a precision of 103 , requiring LumiCal to be a precision device. BeamCal has to operate in a harsh radiation environment and needs radiation hard sensors. Two sensor technologies are considered - Si sensors for LumiCal and GaAs:Cr for BeamCal. A full chain comprising a sensor, fan-out and front-end ASIC was successfully studied in the lab and in a 4.5 GeV electron beam at DESY. Performance parameters like Charge Collection Efficiency (CCE), the Signal to Noise ratio (SIN) were measured. In a second beam test the readout is completed by a multi channel ADC chip and data concentrator.