Dual Harmonic Reference Channel Menu - Ametek 7270 Instruction Manual

Chapter 5, FRONT PANEL OPERATION

5.6.03 Dual Harmonic Reference Channel Menu

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Equations menu (see section 5.3.08), allow the selection of the additional outputs as
variables. For example, it is possible to calculate a value proportional to the ratio of
the X channel output to that of the X
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be output to one of the DAC connectors on the rear panel of the instrument as an
analog voltage.
Naturally, the two harmonics of the signal being measured share a common signal
path and hence controls affecting the signal channel, such as AC Gain and the line
filter controls, apply to both harmonics. Although the full-scale sensitivity setting
can be independently set for both harmonics, the maximum AC Gain that is possible
depends on the greater of these two values.
In dual harmonic mode, the reference channel is controlled by the Dual Harmonic
Reference menu, which differs from the Reference Channel menu used in the other
three modes. In addition, controls are needed for the corresponding output channels,
and so the Output Filters and Output Offset and Expand sub-menus also change. The
relationship of all these menus to Main Menu 1 is shown in figure 5-61. Note that as
with the main menu structure, shown in figure 5-1, it is possible to return to the Main
Display from any menu by pressing the Previous Menu key, but this has been
omitted from figure 5-61 for the sake of clarity.
Figure 5-61, Dual Harmonic Mode Menu Structure
In dual harmonic mode, pressing a key adjacent to the Reference Channel item on
Main Menu 1 accesses the Dual Harmonic Reference menu, shown in figure 5-62.
channel output. With suitable scaling, this can
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