To keep a VICI Pulse Discharge Detector (PDD) operating at peak performance, some parts may need to be replaced periodically. A loss of sensitivity on a PHIC can be caused by contamination of the ground pin. Sensitivity can be restored in some cases by removing and cleaning the ground pin periodically, or in some cases the ground pin must be replaced.
PDD Instruction Manual
Technical Note 620: Cleaning or Replacing a Pulsed Discharge Detector Ground Pin
