Chapter 2 85
Front-Panel Key Reference
Det/Demod
FM  Turning FM demodulation on turns off AM 
demodulation (if it is on). For non-zero spans, a 
100 kHz resolution bandwidth is used during the 
demodulation, regardless of the screen annotation. 
When the span is set to zero span, the displayed 
bandwidth is used. For best results, move the signal to 
be demodulated to within 3 graticules of the top of the 
display. 
Key Access: 
Det/Demod, Demod
Demod View
On Off
  When Demod View (On) is pressed, the vertical scaling of 
the display is in frequency, and marker will read out 
the FM deviation in kHz. When Demod View is On, the 
following functions are not available: Log/Lin (the 
display is always linear and calibrated in Hz), 
YAxis Units, Normalize, Display Line, Peak Excursion, 
and Peak Threshold. In AM Demod, pressing 
Demod View (On) has no effect. The Bluetooth™ FM 
Demod (Option 106) has a fixed vertical scale of 
approximately 40 kHz/Div.
Key Access: 
Det/Demod, Demod
Speaker 
On Off
  Turns the internal speaker on and off. The volume from 
the speaker is controlled by the front-panel volume 
control knob. Selecting AM or FM turns the speaker on. 
Turning AM or FM off, pressing 
Preset when Preset Type 
is set to 
Factory, or cycling the power sets the speaker 
function to off. 
Key Access: 
Det/Demod, Demod
Demod Time
  Allows you to set the time, in non-zero spans, to pause 
and demodulate the signal after each sweep. The 
demodulated signal can be heard during demodulation 
when in 
Speaker (On) mode. (In zero span, 
demodulation is performed (and can be heard) 
throughout the sweep.) In AM, the Video BW is set to 3 
kHz and the Resolution BW is set to 10 kHz. In FM, the 
Video BW is set to 30 kHz and the Resolution BW is set 
to 100 kHz. 
When AM or FM Demod is enabled, the instrument will 
tune to the marker frequency and wait for the Demod to 
take place. For long Demod times, pressing 
Preset when 
Preset Type is set to Factory will abort the Demod 
function. The default value is 500 ms. 
Key Access: 
Det/Demod, Demod