Making Measurements Using Spectrum Analyzer Mode

Demodulating and listening to an AM or FM Signal

5.Change the resolution bandwidth to 100 kHz by pressing m and entering 100 m.

6.Set the signal in the top two divisions of the screen by changing the reference level. Press (-1, and then the step-down key (c93> until the signal is in the top two divisions.

7.Press (AUX], Demod, DEMOD ON OFF (ON), then DEMOD AM FM

(FM). SPEAKER ON OFF is set to ON by the preset function. Use the front-panel volume control to control the speaker’s volume.

For FM demodulation, use FM GAIN to adjust the top-to-bottom screen deviation of the signal with center screen as the reference (0 deviation). The top is the positive deviation and the bottom is the negative deviation. FM gain sensitivity is increased by decreasing the FM gain value. As

the FM gain sensitivity is increased, the volume is increased. Pressing SQUELCH mutes the noise level

&

REF 48.8 dBmVAT 10 dB

m

FMV

AUTO MA

LOG 10 dE/

WA SB

SC FC

CORR

:ENTER 104.903

MHz

 

SPAN

0 Hz

RES BW 100

kHr

VBW 30 CHZ

#SWP 20.0

m5ec

Figure 5-12. Continuous Demodulation of an FM Signal

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