Dear list members:
We have a Micromass Optima with Isochrome continueous flow interface here at
Iowa State University. Recently we are having a vacuum problem. When CRT7
valve is closed, the vacuum reading is only 3.6E-6 (normally it is
about 1E-8 mbar). This happened gradually. If we reopened and then closed the
valve, we can occasionally get a vacuum of 1E-7mbar. But now we can only get
3.6E-6mbar no matter the CRT7 valve is closed or not. We changed a new
copper pad seal, a new knife edge and a new wavy washer, the vacuum is still
3.6E-6mbar. We degassed ion gauge, the reading is still same. When we tried to
degas the ion gauge again, the computer gave us message, it reads "ion gauge
1 bad calibration data" and no vacuum reading in ion gauge display. I
rebooted the computer but everytime when I try to turn the ion gauge on, I
gets the same message. Any suggestions regarding to these two problems will
be greatly appreciated.
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Yuexia Liang
[log in to unmask]         U            1127 HNSB
(515)294-9421(LAB)       S
(515)294-3926(O)         A            Iowa State University