All 8 of the photodiodes in the photodetector array check out electrically.  This was done using the
diode tester function of a multimeter.

Initially a problem was thought to exist with 2 photodiodes - top row, right most two - but this was
traced to a problem with the cabling.  The cabling was measured with the TDR, which seemed to indicate
that the problem was either at the flange or on the in-vacuum side.  Thinking that the seating of the PEEK
2-way coax cables was not good enough, the in-vacuum cable was removed and reseated (thank you Mitchell).
The TDR yielded the same result.  A check of the 2 photodiodes with another set of cables indicated that the
photodiodes were good.  Looking at the in-air cable, which was removed and reseated, two of the connections
came good.  The entire cable assembly (S/N S1301015) was replaced (with S/N S1301016) and all connections
tested okay.

Re-doing the diode test measurement confirmed that the 2 diodes initially thought to be suspect were
okay with the replacement cable.

J. Gleason, P. King