Looked at the QPD Transimpedance Amplifier units at EX, S1102832 and S1102821. We wanted to confirm the board versions. All boards D1001974 are version 2 and have the following configuration: - C15 is removed - R15 is 0 ohms - JP1 has a jumper installed Filiberto Clara
Sorry, I was wrong, but things still look dubious.
From the attached dark spectra of QPD segments, TR_A needs digital dewhite, it doesn't look like TR_B has too much dewhite.
But TR_B still looks like it has some kind of problem, maybe white/dewhite mismatch for seg3 and seg4 (or seg1 and seg2). Needs to be checked later.