Replacing the NPD Bead
Instruction Guide
13
15
Check the NPD leakage current.
a
Display the detector output.
b
Verify that the output (leakage current) is stable and
< 2.0 pA.
If > 2.0 pA, verify bead installation and recheck. If still
high, replace the ceramic insulators; inspect/replace the
collector.
NPD Bead Replacement.book Page 13 Monday, October 13, 2008 2:32 PM