Quick VPT Test Rig meeting - minutes

Date of meeting: 11 October 2002

Venue: RAL

Present: B Kennedy, L Lintern, M Sproston, J Williams

1. Status of rig: Row 3 installed and comissioned, working well.  Row 2 seems rather noisy - MS has changed the LED driver box for this row, but no improvement seen.  Noise seems to be related to oscillations visible in pulse shapes on scope.  More investigation needed.
2. Hardware: ALL working on components for row 4.
3. VPT delivery:  300 new VPTs received from RIE.
4. Analysis: BWK has refitting 300 of the preproduction batch to investigate the proportion of noisy VPTs.  9/300 show multiple peaks, 11/300 high tails (possible discharges) - ie 6.7% noisy.  The production tubes typically have about 10% noisy.  Remaining 200 pre-prod tubes to be refitted next week.

Bruce Kennedy / 05 December 2003