Main Menu 2 - Ametek 7270 Instruction Manual

Chapter 5, FRONT PANEL OPERATION
Reference Frequency Indicator
The display shows the letter "R" centered above the frequency at which the lock-in's
reference channel is currently operating. This makes it possible to quickly identify
the signal of interest from all the other signals present.
Using the Spectral Display Mode
In a typical experiment, if the lock-in amplifier's output is more noisy than might be
expected with the given settings, then the spectrum of the total input signal being
measured can be determined and displayed using the Spectral Display menu. If
strong interfering signals close to the reference frequency are observed, then the
reference frequency should if possible be changed so that operation occurs in a
quieter region. Alternatively it may be possible to switch off the source of the
interference, which might for example be caused by a switched mode power supply
used to power another item of test equipment.
Pressing the Previous Menu key exits the Spectral Display menu and returns to
Main Menu 1.

5.3.24 Main Menu 2

When Main Menu 1 is displayed, pressing the Main menu 2 key accesses
Main Menu 2, which is shown in figure 5-30.
Figure 5-30, Main Menu 2
Main Menu 2 has keys used to access the extended features found in the model 7270,
via a series of sub-menus. The relationship of these sub-menus to Main Menu 2 is
shown in figure 5-31. Note that as with the main menu structure, shown in figure 5-1,
it is possible to return to the Main Display from the sub-menus by pressing the
Main Display key, but this has been omitted from figure 5-31 for the sake of clarity.
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