20200919 ======== Anders prepared a small card with an OP and 100 ohm resistor. Lennart soldered it on the mcm to replace the "damaged" refN op and with a wire from the DAC refN output to the op input on the extra card, since it was suspected that the connection DAC, capacitor pad and op was damaged (We had measured that there is no connection between DAC and OP on the extra card). The current drawn: 3.2A when all is on, which is OK. (Previuosly when no connection DAC and op for refN it was 2.5A). We were then confident that there is now a connection between DAC and OP. We decided therefore to look at data at once. All data with lowest gain and longest shaping. Nominal settings of reference voltages (250,750,1250mV): ch-all-chip2000-34321-ped-nominal-gain0.pdf Settings of reference voltages (200,750,1300mV): ch-all-chip2000-34322-ped-nominal-gain0.pdf Settings of reference voltages (150,750,1350mV): ch-all-chip2000-34323-ped-nominal-gain0.pdf These were all taken with 135 time samples and chip 0. Using the settings 150,750,1350mV, individual channels and events can be found in the files: ch-2000--34323.pdf The main comment is that for channels 1 and 2 is there a clear disturbance at the time of the trigger. With the same settings was data taken for chip 1 and 2: ch-all-chip2001-34329-ped-nominal-gain0.pdf (sorry that the mean and rms is not in the plot) ch-all-chip2002-34331-ped-nominal-gain0.pdf individual channels chip 1 and events can be found in the files: ch-2001--34323.pdf individual channels chip 2 and events can be found in the files: ch-2002--34323.pdf Changed to take data with 1000 time samples. Chip 0: ch-all-chip2000-ped-preamp0gain0shaper0decay0.5.pdf individual channels and events can be found in the files: ch0-2000-10-34335.pdf ch2-2000-10-34336.pdf ch5-2000-10-34337.pdf ch6-2000-10-34338.pdf ch8-2000-10-34339.pdf ch10-2000-10-34340.pdf ch12-2000-10-34341.pdf ch14-2000-11-34342.pdf ch15-2002-17-34342.pdf One comment is the "wave" seen in samples ca 0-200. (sorry did not make plots for all channels). Tried also to take data with chip 3,4 and 7 but did not manage to get any data. System hanged always with the usual signature. This happened as well for chip 0,1 and 2 but not as frequent. Temperature: 67 degrees. Overall comment: The oscillation is gone with 100 ohm resistors on the op output.