Spectrum Analyzerfor Anritsu RF and Microwave Handheld Instruments : AM/FM/PM Analyzer (Option 509) : Amplitude Menu
  
Amplitude Menu
Key Sequence: Amplitude
Amplitude Menu
Scale
Press to set the scaling factor in dB per division. Use the rotary knob, the arrow keys, or the numeric keypad, then press the Enter key.
Power Offset
Press to set the power offset in dB. Use the rotary knob, the arrow keys, or the numeric keypad, then press the Enter key.
Adjust Range
Press to change the reference level if the signal strength is too high (ADC error) or too low.