Configuration Menu - Virtual Reference Mode; Menu Descriptions - Dual Reference Mode; Dual Reference Setup Menu - Ametek 7280 Instruction Manual

5.4.03 Configuration Menu - Virtual Reference Mode

5.5 Menu Descriptions - Dual Reference Mode

5.5.01 Dual Reference Setup Menu

Phase and Ref Phase ±90°, have no effect.
Harmonics greater than unity should not be used in virtual reference mode since the
harmonic number relates to the reference frequency. Nevertheless, detection at
harmonics of the signal frequency is possible by searching for the required harmonic
frequency. For example, if the signal frequency is 1 kHz and a measurement at the
second harmonic is required, set the harmonic to 1st and search for a signal at 2 kHz.
The signals at the OSC OUT connector on the front panel and the REF MON
connector on the rear panel are at the virtual reference frequency.
Since none of the controls on the Reference menu are relevant, it is not possible to
access it.
Figure 5-37, Configuration Menu - Virtual Reference Mode
In virtual reference mode, the choices available on the Configuration menu are as
shown in figure 5-35. To leave virtual reference mode and return to single reference
mode press the Exit Virtual Reference key, to switch to dual reference mode, press
the Dual Reference key, and to switch to dual harmonic mode, press the Dual
Reference key. The remaining controls, including the sub-menus, operate as already
described in section 5.3.13
This completes the description of the virtual reference mode menus.
The dual reference mode allows the model 7280 to measure simultaneously signals
applied to the signal input at two different reference frequencies. One reference must
be supplied to the external reference input, and the second has to be the internal
oscillator.
Chapter 5, FRONT PANEL OPERATION
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