Ametek Dycor Dymaxion Mass Spectrometer, User Manual

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6-8 | Dycor Dymaxion Mass Spectrometer
Cleaning
Open Source
Because of the delicate nature of the open source’s construction, it is impracti-
cal to clean off any deposits that might be on the source. These deposits will
cause the source to lose sensitivity and so the source must be replaced when
these deposits occur.
Mass filter
Deposits can form at the entrance to the mass filter rods when they are oper-
ated at high pressures or over a long period of time.
•
Deposits can sometimes be seen as discolorations on the metal. In
some atmospheres, the rods might be coated with an invisible layer
that will keep the mass filter from operating properly. This will result
in a loss of sensitivity over the full range of the spectrum. If the peaks
disappear at high scan speeds, an insulating layer may have devel-
oped on the surface of the rods.
•
Unless the nature of these discolorations can be identified exactly, the
only sure way of removing them is with a fine abrasive.
•
The entire quadrupole head assembly must be disassembled to clean
the rods.
NOTE

We recommend that the assembly be returned to the factory where the rods
can be cleaned properly.
Figure 6-4. Closed/enclosed quadrupole head.
1. Closed Ion Volume
2. Source Screws
3. Filament Plate
4. Filament Base
5. Barrel Connectors
6. Detector Flange Assembly
7. Mass Filter
8. Ceramic Washer
9. Source
10. Lens 1
11. Lens 2
12. Align Filament Coils with Slots