5Key Reference
86 N9342C/43C/44C User’s Guide
Amptd
Key access: [Amptd]
Activates the reference level function and access 
the associated softkeys to set functions that affect 
the way
  data  on  the  vertical axis is displayed or 
corrected.
Ref level
Key access: [AMPTD] > {Ref level}
Activates the reference level function. 
The reference level is the amplitude power or 
voltage represented by the top graticule on the 
display. Changing the value of the reference level 
changes the absolute amplitude level (in the 
selected amplitude units) of the top graticule line. 
To change the reference level, use the arrow keys, 
the knob, or the numeric keypad. Pressing any 
digit (0 through 9) on the numeric keypad brings 
up the terminator menu.
Attenuation
Key access: [AMPTD] > {Attenuation}
Toggles the input attenuation between Auto or Man.
The input attenuation ranges from 0 dB to 50 dB 
and allows you to set the attenuation level in 1 dB 
increments when attenuation is set to Man. 
The input attenuator, normally coupled to the 
reference level control, reduces the power level of 
the analyzer input signal at the input mixer. The 
attenuator is recoupled when attenuation is set to 
Auto.
CAU-CAUTION
To prevent damage to the input mixer, do not exceed a 
power level of +30 dBm at the input. A granted power 
level for stable sensitive measurement is less than 
20 dBm.