182 5977B Series MSD Troubleshooting and Maintenance Manual
7 Analyzer
Overview
The analyzer with an XTR source (See Figure 39 on page 184)or the analyzer
with a HES (See Figure 44 on page 193) is the heart of the MSD. It ionizes the
sample, filters the ions, and detects them. The sample components exiting the
GC column flow into the ion source. In the ion source, the sample molecules
are ionized and fragmented. The resulting ions are repelled from the ion
source into the quadrupole mass filter. The mass filter allows selected ions to
pass through the filter and strike the detector. The detector generates a signal
current proportional to the number of ions striking it.
The analyzer is attached to the vacuum side of the side plate. The side plate is
hinged for easy access. The ion source and the mass filter are independently
heated. Each is mounted inside a radiator for correct heat distribution.
Each of the parts of the analyzer is discussed in the following material.
The analyzer has four basic components
The analyzer consists of the following components (See Figure 39 on page 184)
or (See Figure 38 on page 183):
• Ion source
• Mass filter
• Detector
• Heaters and radiators