Ion Gun Problems

• Ion gun controller has always had relays clicking, anywhere from every hour or so to every minute or so. Ion current drops momentarily to zero on click
• Today (11/8/12) got essentially no ion current at 2 kV, same settings that were good last week
• sample current monitor ~ 1-2 nA, should be 100's
• no SE detected by hemisphere
• changing offset, obj, cond no help
• pressure sensor DID change with gun standby/sputter
• At 2500 V did get sample current ~ 200 nA. 
• Got SE signal earlier in the afternoon, later no signal.
• Shutdown gun and software, restart, no change.

Fixed

• My bad. When rerouting cables, J8 float voltage was attached to transition lens SHV connector. Therefore gun was floating and operating in a weird mode.
• After fixing cable, 3.6 uA by SCM, also lots of counts.
• Relay clicking, current dropping issue still exists.