Keysight Technologies N9340B User Manual page 89

Preamp
Key access: [AMPTD] > {Preamp}
Toggles the internal preamp between On and Off.
Preamp results in a correction being applied to
compensate for the gain of the preamp at 20 dBm so
that amplitude readings show the actual value at the
input connector.
When the preamp is on, a PA indication appears on the left side of
NO TE
the display.
The preamp is set to on in frequency bands from 
1 MHz to 3 GHz, otherwise the correction is not applied
even though the PA indication still appears.
Scale/DIV
Key access: [AMPTD]
Sets the logarithmic units per vertical graticule division
on the display.
The Scale/Div function is only available when the Scale Type key is
NO TE
set to Log.
Scale Type
Key access: [AMPTD] > {Scale Type}
Toggles the scale type of vertical graticule divisions
between logarithmic and linear.
When Scale Type is set to Log, a logarithmic units is
activated ranging from 1 to 10 dB per division.
When Scale Type is set to Lin, the vertical divisions are
linearly scaled and the default amplitude units are volts.
The top of the display is set to the reference-level value
and the bottom graticule becomes zero volts. (Each
division of the graticule is one-tenth of the reference
level in volts.)
Key Reference
Amplitude
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